MODERN  PIGMENTS 


AND    THEIR 


YEHICLES 


THEIR    PROPERTIES    AND    USES  CON- 
SIDERED  MAINLY  FROM  THE 
PRACTICAL    SIDE 

AND 

HOW  TO  MAKE  TINTS  FROM  THEM 


BY 

FREDERICK   MAIRE 

i  \ 

EX-EDITOK  OF  "PAINTING  AND  DECORATING,"  AUTHOR 

OF  THE  "MODERN  WOOD  FINISHER,"  THE 

"MODERN  GRAINER" 


FIRST  EDITION 

FIRST    THOUSAND 


NEW   YORK 

JOHN   WILEY   &   SONS 
LONDON  :   CHAPMAN   &    HALL,  LIMITED 

1908 


t 


COPYKIOHT.    1907. 
BY 

FREDERICK   MAIRE 


Stanbope 

H.   OILSON   COMPANY 
BOSTON,   U.  8.  A. 


PREFACE 


IT  is  to  be  regretted  that  notwithstanding  it  is  a  matter 
of  prime  importance  that  both  dealers  in  painters'  supplies 
and  users  of  the  same  —  the  painters  and  decorators  — 
should  be  well  posted  about  the  materials  they  handle,  the 
vast  majority  have  but  the  faintest  ideas  concerning 
the  properties  of  pigments.  One  would  naturally  suppose 
that  dealers  ought  to  know  all  about  them,  their  values, 
cost  of  production,  qualities  and  defects.  Without 
such  knowledge  they  cannot  truthfully  answer  the 
questions  daily  put  to  them.  This  ignorance  has  made 
it  possible  for  unscrupulous  manufacturers  to  palm  off 
almost  anything  upon  them.  Every  manufacturer  and 
dealer  has  been  a  law  unto  himself,  each  differing  from 
nearly  everyone  else  in  the  trade.  This  lack  of  standards 
was  really  due  to  the  indifference  caused  by  the  lack  of 
knowledge  on  the  part  of  both  dealers  and  consumers. 
It  has  enabled  the  unprincipled  to  fleece  an  unsuspecting 
public  out  of  millions  of  dollars. 

Now  that  the  public  is  being  made  fully  aware  of  what 
they  buy  in  the  way  of  food,  and  that  the  general  govern- 
ment and  most  of  the  states  are  working  together  in 
enforcing  laws  which  require  manufacturers  to  state 
upon  labels  placed  upon  packages  an  exact  statement  of 
what  they  contain,  it  is  to  be  hoped  that  the  same  pro- 
tection will  be  extended  to  all  other  compounded  material 
in  the  paint  line  which  is  subject  to  adulteration. 

The  blame  for  adulteration  does  not  rest  upon  the 
shoulders  of  the  manufacturers  and  dealers  only.  Igno- 

iii 


iv  PREFACE 

ranee  of  what  constitutes  the  value  of  an  article  and  a 
desire  on  the  part  of  consumers  to  obtain  it  at  a  cost 
below  what  it  is  worth  are  also  very  strong  factors  — 
possibly  the  main  ones  why  goods  are  adulterated  at  all. 
Manufacturers  and  dealers  would  not  undertake  to 
manufacture  or  sell  material  for  which  there  would  be  no 
demand. 

The  Master  Painters'  Association  has  done  some 
excellent  work  in  past  years  to  open  the  eyes  of  painters, 
and  through  its  efforts  in  showing  up  the  rottenness  in  the 
paint  trade  existing  at  the  time  of  its  inception  a  great 
change  for  the  better  has  been  brought  about. 

The  trade  journals,  however,  have  done  even  more 
real  good  by  bringing  this  work  of  the  association  to  the 
knowledge  of  thousands  of  those  painters  who  are  not 
members  of  the  association  and  who  otherwise  would 
never  have  heard  of  it.  Thanks  to  this  agitation  which 
has  been  going  on  for  the  past  eighteen  years,  the  paint 
situation  is  in  a  much  healthier  condition  to-day. 
Standards  of  quality  are  being  established,  and  it  is 
possible  to  obtain  colors  dry,  ground  in  oil,  Japan  or 
water,  which  are  exactly  what  the  label  represents  them 
to  be. 

It  is  not  within  the  scope  of  this  little  book  to  go  into 
the  detective  business  nor  to  make  a  specialty  of  exposing 
the  tricks  of  trade.  Its  purpose  is  to  give  a  brief  and 
concise  history  of  all  valuable  pigments  useful  in  paint- 
ing —  the  main  sources  of  their  derivation  and  supply; 
their  properties  and  chief  uses;  their  good  qualities  and 
their  defects  will  be  pointed  out  and  incidentally  there 
will  be  presented  the  best  methods  of  detecting  adultera- 
tion. 

While  tons  of  literature  have  been  issued  by  the  trade 
journals  and  in  book  form,  very  little  has  been  written 


PREFACE  V 

upon  pigments,  and  most  of  that  has  been  in  short  sketches 
and  merely  as  a  side  issue  to  the  main  subject  matter  of 
the  volumes  containing  them. 

Some  excellent  books  on  pigments  have  been  published 
in  England  and  Germany.  These  were  written  by 
chemists  and  are  of  use  to  manufacturers  in  particular. 
They  mainly  treat  what  may  be  called  the  scientific  side, 
the  practical  being  only  treated  incidentally  or  ignored 
entirely.  Of  this  character  are  such  admirable  works  as 
Field's  Chromatography.  Its  high  cost,  even  if  it  treated 
pigments  more  fully  from  the  consumer's  viewpoint, 
would  prevent  its  purchase  by  the  bulk  of  those  who 
otherwise  would  be  interested  in  it  and  no  doubt  procure  it. 

It  is  impossible  in  as  small  a  volume  as  this  to  enter 
into  the  chemistry  of  pigments  nor  into  some  of  the  intri- 
cate details  of  manufacture  and  preparations  for  use, 
except  in  the  briefest  manner  that  will  give  the  reader 
a  fair  idea  of  its  composition.  This  is  about  all  that 
painters  or  dealers  require  to  know  of  the  chemical  side  of 
pigments.  Additional  details  would  be  of  no  importance, 
and  none  outside  a  manufacturer  of  colors  would  be 
interested  in  them.  This  manual  is  written  for  the  men 
who  use  or  sell  pigments  and  who  mainly  want  to  know 
what  they  can  expect  of  them. 

The  author  has  made  use  of  the  best  that  has  been  said 
upon  the  subject  matter  in  the  past.  He  has  consulted 
some  of  the  best  authorities  and  had  access  to  nearly 
everything  that  has  been  published  on  pigments,  many  of 
these  books  being  now  out  of  print.  He  was  also  very 
fortunate  in  that  for  a  few  years  he  had  the  pleasure  of 
having  intercourse  almost  daily  with  the  late  lamented  Wm. 
C.  Wilson  of  Philadelphia,  who  at  that  time  was  probably 
the  best  posted  man  on  pigments  in  America.  The 
information  thus  obtained  has  been  largely  drawn  upon. 


vi  PREFACE 

This  little  book  will  be  of  value  to  the  young  man  who 
is  starting  out  to  learn  the  painter's  trade.  It  will 
teach  him  what  he  ought  to  know  about  paints  and 
what  he  will  never  learn  from  the  average  journeyman 
who  is  usually  reticent  and  may  very  likely  not  know 
enough  about  pigments  to  answer  a  novice's  queries. 
It  will  be  useful  to  many  painters  who  have  never  had 
an  opportunity  to  study  the  matter  of  pigments,  except 
in  a  haphazard  sort  of  a  way  —  without  system  and  with 
much  guess-work.  As  to  the  dealers,  many  of  them  are 
druggists  who  have  a  fair  knowledge  of  chemistry. 
These  will  find  the  chemical  details  sufficient  to  give  the 
information  that  is  wanted.  Other  dealers  not  so  well 
informed  find  also  enough  explanation  to  enable  them 
to  know  if  they  are  buying  the  right  goods  or  paying  a 
fair  price. 

It  is  probable  that  errors  have  crept  in  and  will  crop 
out  when  this  book  comes  out  in  print.  Good  care  has 
been  taken  that  there  be  no  glaring  ones,  but  it  is  still 
possible  that  some  may  inadvertently  have  been  over- 
looked. Be  that  as  it  may,  infallibility  is  not  claimed, 
but  the  author  has  given  out  what  he  honestly  thinks 
is  reliable.  Such  as  it  is,  this  little  book  is  confidently 
submitted  to  an  indulgent  public. 

F.  MAIRE.     • 

HAMILTON,  ILLINOIS. 
Aug.  30,  1907. 


CONTENTS 


CHAPTER   I 

PAGE 

PREFACE    ....  hi 


PRELIMINARIES 


Definition  of  the  word  "  pigment."  —  Some  substances  are  real 
pigments  in  water,  but  only  so  by  courtesy  in  oil.  —  Synopsis 
of  the  manner  in  which  the  subject  matter  is  to  be  treated  in 
succeeding  chapters. 


CHAPTER   II 
WHITE  PIGMENTS 8 

Introduction.  —  White  lead,  history,  chemistry,  and  manu- 
facture. —  Dutch  process;  stack  method  of  corrosion,  cylinder 
method,  sulphate  of  lead,  sublimed  lead.  —  Dahl  process;  prop- 
erties and  uses.  —  Blow  pipe  and  other  tests  for  impurities. 

CHAPTER    III 
WHITE  PIGMENTS  (Continued)      32 

Zinc  white;  its  history  and  chemistry,  its  properties  and  uses. 

CHAPTER   IV 
WHITE  PIGMENTS  (Continued)      40 

Earth  whites ;  their  general  characteristics.  —  Whiting  (car- 
bonate of  lime) ;  properties  and  uses.  —  China  clay  (kaolin) ; 
properties  and  uses.  —  Gypsum  (sulphate  of  lime) ;  properties 
and  uses.  —  Silicate  earths;  properties  and  uses.  —  Silver 
white;  properties  and  uses.  —  Baryta  white  (sulphate  of 
barium) ;  properties  and  uses. 

vii 


viii  CONTENTS 

CHAPTER   V 

PAGE 

YELLOW  PIGMENTS 57 

Ochers;  history  and  early  use  made  of  them,  methods  of 
mining  and  preparing  for  market,  divided  into  two  classes, 
the  silicious  and  aluminous,  various  characteristics,  proper- 
ties and  uses  of  each.  —  Grinding  colors  in  shops,  no  econo- 
my therein.  —  American  ochers;  their  properties  and  uses. 
—  Artificially  made  ochers. 

CHAPTER   VI 
YELLOW  PIGMENTS  (Continued) 73 

The  chrome  yellows ;  their    various  tones.  —  Medium  chrome 
yellow,  only  the  chromate  of  lead.  —  Canary  and  lemon  chrome 
yellows.  —  Baryta     lemon     chrome     yellow ;     characteristics,    . 
properties  and   uses.  —  Adulterations;   how  to  detect  them. 

—  Comparisons  and  the  judging  of  values  by  the  scale  test.  — 
Full  directions  for  making  it.  —  Useful  for  many  other  colors. 

CHAPTER  VII 
YELLOW  PIGMENTS  (Continued) 86 

Gamboge;  production,  properties  and  uses. — Aureolin  or  cobalt 
yellow;  properties  and  uses.  —  Indian  yellow;  properties  and 
uses.  —  Naples  yellow;  production,  properties  and  uses. — 
Dutch  pink,  yellow  lake,  Italian  pink,  quercitron,  etc.;  pro- 
perties and  uses.  —  Cadmium  yellow ;  properties  and  uses.  — 
King's  yellow  or  orpiment;  properties  and  uses. 

CHAPTER  VIII 

RED  PIGMENTS 95 

Vermilion.  —  Quick  silver  vermilion;  its  history,  chemistry 
and  manufacture ;  properties  and  uses,  adulteration.  —  The 
imitation  or  vermilion  reds ;  peculiarities,  properties  and  uses. 

—  American  vermilion;  properties  and  uses. 

CHAPTER   IX 
RED  PIGMENTS  (Continued} 106 

Venetian  red;  history  and  manufacture,  characteristics,  proper- 
ties and  uses.  —  Indian  reds;  characteristics,  properties  and 
uses.  —  Tuscan  reds ;  properties  and  uses.  —  Red  oxide  of  iron ; 
characteristics,  properties  and  uses. 


CONTENTS  ix 

CHAPTER   X 

PAGE 

RED  PIGMENTS  (Continued.') 116 

Red  lead;  its  chemistry  and  manufacture,  properties  and 
uses.  —  Lakes;  what  they  are.  —  Alizarin  and  purpurin;  their 
uses  in  the  manufacture  of  lakes.  —  Rose  pink;  properties  and 
uses.  —  Rose  lake;  properties  and  uses.  —  Madder  lakes; 
include  all  shades  and  varieties  of  red  lakes  made  from  alizarin 
and  purpurin,  many  sold  under  proprietary  names.  — 
Indian  lake;  properties  and  uses.  —  Carmine  and  the  cochineal 
lakes;  characteristics,  properties  and  uses.  —  Red  ochers;  what 
they  are. 

CHAPTER  XI 
GREEN  PIGMENTS 129 

Chrome  greens;  composition,  properties  and  uses.  —  All  greens 
under  proprietary  names  are  chrome  greens.  —  Green  oxide  of 
chromium,  true  chrome  green;  properties  and  uses.  —  Cobalt 
green  or  zinc  green;  preparation,  properties  and  uses. —  Viri- 
dian;  properties  and  uses. 

CHAPTER   XII 
GREEN  PIGMENTS  (Continued)      139 

Terre  verte;  properties  and  uses.  —  Verdigris;  derivation,  proper- 
ties and  uses.  —  Paris  or  emerald  green;  chemistry,  properties 
and  uses.  —  Malachite;  properties  and  uses.  —  Scheele's  green; 
properties  and  uses. 

CHAPTER  XIII 
BLUE  PIGMENTS       145 

Ultramarine  blue;  history,  character,  properties  and  uses. — 
Prussian  blue;  chemical  constituents,  preparation,  properties 
and  uses.  —  Chinese  (Prussian)  soluble  blue;  properties  and 
uses. 

CHAPTER   XIV 
BLUE  PIGMENTS     (Continued)       152 

Cobalt  blue;  preparation,  properties  and  uses.  The  artificially 
prepared  cobalt  blue.  —  Cceruleum ;  properties  and  uses.  — 
Chessylite;  properties  and  uses.  —  Smalt;  properties  and  uses. 


x  CONTENTS 

CHAPTER   XV 

PAGE 

BROWN  PIGMENTS 156 

Umbers.  —  Raw  umber;  characteristics,  properties  and  uses.  — 
Burnt  umber;  properties  and  uses.  —  Siennas.  —  Raw  sienna; 
where  obtained,  preparation,  properties  and  uses.  —  Burnt 
sienna;  properties  and  uses.  —  Vandyke  brown;  properties  and 
uses.  —  The  metallic  browns;  provenance,  properties  and 
uses.  —  Spanish  brown;  properties  and  uses. 

CHAPTER   XVI 
BLACK  PIGMENTS 170 

Lamp  black;  characteristics,  manufacture,  properties  and  uses.  — 
Carbon  or  gas  black;  properties  and  uses.  —  Ivory  black. — 
Coach  black.  —  Drop  black.  —  One  and  the  same ;  preparation, 
properties  and  uses.  —  Charcoal  black  or  blue  black ;  properties 
and  uses.  —  Graphite  or  plumbago;  properties  and  uses. 

CHAPTER   XVII 
SYNONYMS 181 

A  table  to  facilitate  the  finding  of  pigments  known  under  various 
names. 

CHAPTER   XVIII 
VEHICLES  USED  IN  GRINDING  PIGMENTS  AND  IN  APPLYING  THEM     189 

What  vehicles  are.  —  Raw  linseed  oil.  —  What  a  drying  oil  is.  — 
What  a  fixed  oil  is.  —  The  only  ones  of  use  for  exposed  paint- 
ing. —  The  provenance  of  linseed  oil ;  its  manufacture  and 
preparation  for  use.  —  How  linseed  oil  dries ;  its  proper- 
ties.—  Boiled  linseed  oil;  its  properties.  —  Nitric  acid  and 
other  tests  for  impurities.  —  Poppyseed  oil;  characteristics, 
properties  and  uses. 

CHAPTER   XIX 
VEHICLES  (Continued)         206 

The  volatile  oils;  what  they  are;  their  properties  and  uses 
in  paint  vehicles.  —  Spirits  of  turpentine;  how  obtained;  its 
diuretic  properties.  —  Naphtha  and  benzine;  properties  and 
uses.  —  All  volatile  oils  solvent  of  gum-resins  used  as  such  in 
varnish  making. 


CONTENTS  xi 

CHAPTER   XX 

PAGE 

VEHICLES  (Continued)         211 

Varnishes,  japans  and  alcoholic  shellac  solutions.  —  Varnishes; 
what  they  are;  their  properties  and  uses  as  binders  and  vehi- 
cles. —  Japans;' some  confusion  as  to  what  they  are;  their  use 
as  vehicles,  driers,  alcoholic  shellac  solutions;  properties  and 


CHAPTER   XXI 

SUBSTANCES  USED  AS  CORRECTIVES  AND  BINDERS 217 

Waxes.  —  Beeswax  used  in  encaustic  painting  in  earliest  civiliza- 
tion. —  The  vegetable  waxes.  —  The  paraffin  waxes. 

CHAPTER   XXII 

SUBSTANCES    USED    TO    BIND    PIGMENTS    IN  CONNECTION    WITH 

VEHICLES       220 

Glues;  manufacture,  properties  and  uses.  —  Gum  arabic;  prove- 
nance, properties  and  uses.  —  Starch,  dextrin,  honey,  sugar, 
molasses  and  glycerine.  —  Their  properties  and  uses. 

CHAPTER   XXIII 

DRIERS  AND  SICCATIVES 229 

Boiled  linseed  oil  as  a  siccative;  properties  and  uses.  —  The  lead 
oxides ;  the  oxides  of  manganese.  —  Acetate  of  lead.  —  Sulphate 
of  zinc.  —  Their  action  upon  linseed  oil  and  other  fixed  oils 
considered. 

CHAPTER   XXIV 
THE  COMPOUNDING  OF  PIGMENTS ..."     235 

Philosophy  of  color.  —  Rules  to  guide  one  in  the  compounding 
of  tints. 

CHAPTER   XXV 

A  LIST  OF  THE  PRINCIPAL  TINTS   AND  OF  PIGMENTS  REQUIRED 

TO  MAKE  THEM 243 

A  few  cautionary  words  followed  by  the  list  of  tints. 


F  THE     "        \ 

UNIVERSITY  ) 

OF  / 


MODERN  PIGMENTS  AND  THEIR  VEHICLES 
THEIR  PROPERTIES  AND  USES 


CHAPTER  I 

PRELIMINARIES 

IN  subsequent  chapters  it  is  intended  to  take  up  a  study 
of  the  various  pigments  which  are  used  in  ordinary 
painting,  as  well  as  those  employed  by  decorators  for 
either  distemper  or  oil  painting;  those  used  by  coach 
and  car  painters  will  also  be  reviewed.  The  whole  field 
will  be  covered,  with  possibly  the  exception  of  a  few  pig- 
ments which  have  become  obsolete,  and  which  have  been 
replaced  by  better  ones. 

The  vehicles  which  are  used  in  the  application  of  pig- 
ments will  also  be  noticed,  as  in  some  respects  they  are 
really  of  more  importance  than  the  pigments  themselves. 
Binding  substances  and  correctives  will  also  be  described, 
and  their  character  and  uses  noted. 

The  word  "  pigment  "  is  applied  to  coloring  substances 
which,  when  mixed  with  suitable  vehicles,  form  paints.  It 
means  "  color,"  the  word  "  color  "  being  used  indifferently 
to  mean  a  compound  of  various  pigments,  or  a  pigment 
which  has  been  ground  ready  for  use;  the  various  pig- 
ments put  up  in  cans  and  found  for  sale  at  the  supply 
stores  are  commonly  known  by  that  name.  No  matter 

1 


2  MODERN  PIGMENTS 

what  medium  has  been  used  in  the  grinding  of  pigments, 
be  it  linseed  oil,  japan,  varnish,  or  water,  all  are  known 
as  " colors"  either  simple  or  compounded.  The  word 
"pigment"  is  therefore  much  more  restricted  than 
that  of  " color." 

Strange  as  it  may  appear,  this  word  has  not  yet 
received  its  final  definition.  It  is  vaguely  applied 
to  designate  any  substance  that  may  be  used  in  the 
preparation  of  paint,  fillers  used  in  wood  finishing, 
etc.  It  is  given  to  any  solid  substance  used  in  com- 
pounds, and  is  replacing  that  word  in  paint  parlance 
at  least. 

Strictly  speaking,  the  name  of  pigment  should  never 
be  given  to  any  substance  unless  it  has  the  inherent 
power  of  its  own  to  impart  color  to  other  substances  with 
which  it  may  be  mixed.  Originally  it  was  used  in  this 
strict  sense  only,  and  it  should  be  so  restricted.  As  it  is 
now,  the  adjunct  substances  possessing  no  coloring  matter 
of  their  own  which  are  usually  added  to  true  pigments 
with  no  other  purpose  in  view  than  that  of  adding  weight 
without  changing  the  original  color  of  the  pigments  in 
combination,  are  all  called  pigments  too.  It  is  a  mis- 
nomer. Possessing  no  coloring  matter,  the  makeweights 
are  certainly  not  entitled  to  the  name. 

Correctives  —  sometimes  useful  adjuncts  to  a  pigment 
—  are  frequently  of  the  same  colorless  character  as  the 
makeweights,  and  therefore  not  entitled  to  be  classed 
with  them.  To  illustrate  exactly  what  is  meant,  the 
following  example  is  given:  Starch  and  glue  are  solid 
substances,  but  after  they  have  been  converted  into  thin 
paste  by  the  addition  of  hot  water  they  are  colorless,  and 
when  they  have  been  mixed  with  whiting  or  zinc  or  any 
"colors,"  a  distemper  color  has  been  prepared  of  which 
either  may  form  a  component  part,  though  not  as  a  pig- 


PRELIMINARIES  3 

ment ;  the  addition  does  not  change  the  color  of  the  com- 
pound in  the  least. 

Here  is  another  example:  Liquid  fillers,  and  fillers  for 
the  light  hard  woods,  contain  some  transparent  solid  sub- 
stance, such  as  very  finely  ground  silex,  quartz,  etc.;  the 
manufacturer  in  his  pamphlets  calls  it  the  pigment  part  of 
the  filler.  He  uses  it  in  this  connection  actually  in  place 
of  the  word  "solid."  This  is  wrong,  and  befogs  the  real 
meaning  of  the  word,  which  originally  seemed  admirably 
adapted  to  express  the  thought  of  coloring  matter. 

By  courtesy  some  few  substances  will  be  designated  as 
pigments  that  do  not  possess  any  coloring  matter  of  their 
own  to  impart  to  other  materials  with  which  they  are 
mixed.  For  instance,  barytes  has  no  coloring  matter  to 
impart  to  other  pigments  ground  with  it  in  oil  or  japan, 
but  when  used  alone  in  water  it  has  a  white  color.  Several 
such  substances  which  do  not  deserve  to  be  classed  as  colors 
when  mixed  in  oil,  have  coloring  when  mixed  with  water; 
and  to  save  a  double  definition  of  them,  the  term  " pig- 
ment," which  is  applicable  to  them  when  in  water  but 
which  would  not  apply  when  mixed  in  oil,  is  nevertheless 
retained  in  this  instance,  but  to  which  they  are  really 
no  more  entitled  than  is  starch  or  glue.  For  similar 
reasons,  carbonate  of  lime  (whiting),  sulphate  of  lime 
(gypsum) ,  finely  powdered  silicate  stone  or  earths  (silver 
white  or  English  kalsomine),  will  also  be  included  in  the 
list  of  pigments,  for  they  are  properly  so  called  when  in 
water  (if  not  in  oil). 

To  facilitate  the  search  of  any  particular  pigment,  so 
that  they  can  be  readily  found  without  even  taking  the 
trouble  to  look  them  up  in  the  index,  these  have  been 
placed  in  groups  of  the  principal  colors,  and  all  pigments 
of  that  tone  or  order  will  be  found  under  the  proper 
heading  in  the  class  to  which  they  belong.  The  principal 


4  MODERN   PIGMENTS 

pigment,  or  that  which  is  mostly  used,  will  be  placed  at  the 
head  of  the  list,  and  others  will  follow  in  the  order  of 
their  usefulness. 

Under  each  will  be  given,  as  far  as  practicable,  a  brief 
historical  sketch  of  its  origin  and  derivation,  its  manu- 
facture and  preparation  for  market,  its  properties  and 
uses,  the  best  and  easiest  methods  of  detection  if  subject 
to  adulteration,  the  enumeration  of  other  substances 
which  are  injurious  and  with  which  it  should  never  be 
combined,  and,  lastly,  any  other  points  of  especial  interest. 

It  was  stated  in  the  preface  that  it  was  not  within  the 
scope  of  this  book  to  treat  the  subject  matter  "pigments  " 
from  the  standpoint  of  the  chemist  or  color-maker,  and 
reasons  were  given  why;  but  the  chemistry  of  most  all  the 
pigment  will  at  least  be  briefly  noticed  —  simply  the 
giving  of  their  component  parts,  or,  where  they  have  a 
recognized  formula,  the  giving  of  that.  In  a  few  of  the 
better  known  ones,  a  full  enumeration  of  their  constituent 
elements  will  be  given,  as  this  is  frequently  an  index  as  to 
their  character;  but  when  the  desirability  for  this  occurs, 
it  will  be  done  in  a  way  that  can  be  understood  by  those 
not  familiar  with  chemistry,  and  in  words  as  free  of 
technical  expressions  as  possible.  A  person  needs  not  to 
be  a  chemist  nor  familiar  with  that  science  to  understand 
a  great  deal  of  what  constitutes  the  chemistry  of  paint; 
good  common  sense  will  go  a  long  way  with  the  reader 
to  enable  him  to  recognize  the  true  from  the  false. 

The  researches  and  experiments  made  in  the  field  of 
color  by  eminent  scientists  within  the  last  century  — 
many  by  men  of  the  greatest  ability,  and  who  were  guided 
more  by  a  love  of  attaining  knowledge  than  with  the 
monetary  inducements  —  have  made  the  task  of  writing 
up  "  pigments  "  a  comparatively  easy  one.  The  author 
cannot  claim  a  great  amount  of  originality,  nor  has  he 


PRELIMINARIES  5 

made  any  great  discovery  himself,  so  that  what  he  has 
to  say  is  none  of  his  finding  out,  nor  is  it  the  first  time 
that  it  has  appeared  in  print.  The  present  treatise  is,  in 
the  main,  one  of  compilation  and  arrangement.  Nearly 
half  a  century  of  practical  handling  of  pigments,  and 
experimenting  with  them  in  paint  factories  and  in  the 
ordinary  practice  of  the  paint  shop,  have  helped  him 
form  some  decided  opinions  about  the  application  and 
mixing  of  most  pigments,  and  upon  this  fund  of  knowl- 
edge the  writer  has  drawn  freely  and  without  stint, 
and  it  is  embodied  in  this  treatise  with  that  of  others. 

A  good  knowledge  of  the  properties  of  pigments  is 
imperatively  demanded  of  any  one  who  wishes  to  be  up 
in  the  paint  business,  either  as  a  dealer  or  user.  There 
is  much  to  be  learned  about  the  proper  mixing  of  pig- 
ments and  about  vehicles  suitable  for  the  various  pur- 
poses: the  future  has  a  fine  field  for  research  in  that 
direction,  for  we  do  not  know  it  all  by  long  odds,  and  there 
remains  much  to  be  revealed  at  some  time  or  another. 
Much  of  what  is  known  now  is  not  of  such  a  character 
that  one  can  absolutely  rely  upon  it;  hence  so  many 
opinions  which  are  diametrically  opposed  to  each  other 
about  the  preparation  or  application  of  the  simplest  of 
mixtures.  Humiliating  as  it  may  be  to  one  who  has 
made  a  lifetime  study  of  the  paint  business,  the  truth 
requires  and  compels  one  to  acknowledge  as  much  as 
appears  above,  for  what  now  passes  as  orthodox  in  many 
good  paint  shops,  will  be  classed  as  rank  heresy  in  others 
of  equally  good  repute.  Therefore  it  is  only  by  a  thorough 
and  intimate  knowledge  of  pigments,  vehicles,  and  con- 
ditions that  any  one  can  hope  to  grope  to  half-way 
certainty  in  sundry  instances,  and  to  a  fuller  one  in  a  very 
few  others.  If  it  is  so  hard  to  get  at  the  truth  for  those 
who  are  constantly  studying,  what  must  the  practice  be 


6  MODERN  PIGMENTS 

of  those  who  do  not  study?  Assuredly  they  can  have 
nothing  but  routine  and  guesswork. 

There  is  much  to  be  learned,  —  all  are  agreed  upon  that. 
Chemists  in  the  employ  of  paint  manufacturers,  and 
others  who  are  inclined  to  researches  in  the  same  direction, 
usually  make  these  their  life  hobbies;  but  as  it  is  com- 
monly on  the  side  from  their  regular  work,  they  are 
somewhat  hampered ;  but  every  once  in  a  while  one  hits 
upon  some  process  or  other  which  is  beneficial  and  help- 
ful in  the  manner  of  fixing  the  coloring  matter  contained 
in  certain  pigments  more  permanently  than  was  ever 
done  before,  or  indeed  it  may  be  the  discovery  of  entirely 
new  ones.  Much  has  been  done,  but  much  still  remains 
to  be  done  by  the  chemists.  On  the  practical  side, 
however,  there  is  still  a  great  deal  to  be  learned ;  and  here 
is  work  for  the  thinking  painters,  and  also  for  the  asso- 
ciations of  master  painters,  who  can  do  a  great  deal  of 
good  by  bringing  together  those  who,  while  they  differ 
in  opinions,  can  compare  results,  and  thus  aid  in  getting 
at  true  solutions  of  vexatious  questions. 

Many  important  discoveries  of  the  chemists  were 
prompted  by  suggestions  made  to  them  by  the  tests  of 
practical  men.  Theoretical  chemists  and  practical  men 
generally  cannot  afford  to  work  aloof  from  each  other. 
Either  one  without  the  help  of  the  other  is  more  or  less 
of  a  failure.  Theory  must  be  proved  by  practical  tests 
to  be  right.  Many  chemists  are  too  apt  to  belittle  the 
value  of  suggestions  made  by  well-posted  painters,  and 
to  regard  them  too  much  in  the  light  of  useful  machines 
for  the  proper  application  of  paint.  There  can  be  little 
wonder  that  many  of  their  compounds  and  discoveries 
of  new  preparations  prove  of  no  practical  value.  The 
Patent  Office  at  Washington,  D.C.,  is  a  cemetery  where 
thousands  of  inventions  in  the  paint  line  lie  buried, 


PRELIMINARIES  7 

unknown  and  undisturbed,  simply  because  of  their 
impracticability. 

On  the  other  hand,  the  painter  too  often  looks  at  the 
researches  of  scientific  men  with  a  sneer  and  turns  up  his 
nose  at  them.  All  would  find  it  advantageous  to  study 
the  writings,  and  make  use  of  the  information  they  would 
find  in  them,  of  such  men  as  Chevreuil,  G.  Field,  L.  E. 
Andes,  J.  Lefort,  A.  H.  Church,  and  many  others.  Unfor- 
tunately, some  of  these  men's  works  are  now  out  of 
print,  and  are  to  be  found  only  in  a  few  of  the  larger 
public  libraries. 

The  German  language  is  richer  with  valuable  scientific 
works  on  pigments  than  is  the  English,  but  these  are 
very  expensive,  and  mainly  of  interest  to  men  well  up  in 
chemistry.  It  is  hoped  that  translations  of  some  of  their 
best  works  may  be  made,  adapted  to  the  popular 
understanding. 


CHAPTER  II 
WHITE   PIGMENTS 

As  it  was  stated  in  the  preceding  chapter,  to  facilitate 
the  search  for  any  one  given  pigment,  all  have  been 
classed  into  groups  of  certain  colors,  and  within  each 
will  be  found  all  which  belong  to  it  by  being  nearer  in 
tone  than  to  any  other  group.  It  is  fitting  to  commence 
with  the  whites,  as  this  group  is  the  most  important  of 
all.  The  whites  are  not  only  important  to  the  painter 
on  account  of  its  "  self  "  color  and  the  one  self  color 
mostly  used  in  painting,  and  rightly  so  on  account  of 
cleanly  tone  and  brightening  effect,  but  also  because  the 
whites  form  the  base  upon  which  nearly  all  tints  are 
made  by  the  addition  of  colored  pigments. 

The  ideal  white  pigment,  is  probably  present  to  the  aver- 
age painter's  mind,  but  the  realization  of  it,  as  yet,  has 
been  far  from  the  ideal  one.  Every  practical  user  of  paint 
who  has  given  much  thought  to  it,  has  some  such  ideal 
pigment  mapped  out  in  his  head.  He  has  ideas  of  what 
it  should  be  like,  —  all  good  qualities,  with  none  bad,  — 
but  when  he  goes  out  among  the  realities  of  life  and  looks, 
he  does  not  find  it.  His  ideal  white  pigment  is  to  be  found 
only  in  his  mind.  A  feeble  portion  of  the  good  qualities 
desired  in  a  white  are  to  be  found  unassociated  with  some 
very  bad  ones  in  any  one  white  pigment.  In  actual 
practice  it  turns  out  that  for  every  good  quality  shown, 
there  will  be  found  a  counterbalancing  defect  which 
will  prove  a  thorn  in  the  flesh. 

8 


WHITE  PIGMENTS  9 

The  above  is  written  for  the  purpose  of  preparing  the 
reader  for  the  defects  which  are  found  in  all  the  most 
prominent  white  pigments,  and  also  to  guard  him  against 
over-confidence  or  extravagant  expectations  from  the 
use  of  any. 

WHITE  LEAD 
History 

White  lead  is  the  most  prominent  and  best  known 
of  any  of  the  white  pigments  on  the  list.  There  are  few 
persons  to  be  found,  even  outside  of  those  connected  with 
the  paint  trade,  but  who  are  not  more  or  less  familiar  with 
or  at  least  have  heard  of  it  in  some  way.  Mankind  has 
known  white  lead  a  long  time.  It  is  of  very  ancient 
antecedents.  That  the  oldest  civilizations  knew  it,  is 
evidenced  by  the  remains  of  their  pottery  —  the.  glazing 
upon  it  being  obtainable  only  by  the  use  of  white  lead. 
Such  Latin  writers  as  Pliny  and  Vitruvius  give  the 
process  of  its  manufacture  from  lead  and  vinegar.  It 
was  then  known  under  various  names,  some  of  which 
have  come  down  to  our  own  times,  and  which  are  used 
to  designate  it  to-day.  For  instance,  "Cerusa,  minium 
album  "  in  Continental  Europe  is  still  known  as  ceruse 
and  white  minium.  Recent  excavations  have  brought 
to  light  a  number  of  well-preserved  specimens  of  white 
lead  which  show  that  it  must  have  been  an  article  of 
common  use  in  ancient  Greece  and  Egypt. 

The  above  details  are  given  because  many  people 
suppose  white  lead  to  be  a  comparatively  new  dis- 
covery, or  at  best  dating  back  but  a  few  centuries.  It 
is  true,  however,  that  only  a  little  over  two  hundred 
years  have  elapsed  since  white  lead  commenced  to  be 
manufactured  on  a  large  scale  by  what  is  known  as  the 


10  MODERN  PIGMENTS 

"Dutch  Process."  Really,  the  principles  of  that  system 
are  the  same  as  those  described  by  Pliny,  the  only  dif- 
ference being  that  a  different  application  of  the  same  is 
made  use  of  in  the  Dutch  process. 

While  Holland  has  the  honor  of  having  given  its  name 
to  the  process  that  is  usually  employed  in  the  manufacture 
of  white  lead  to-day,  that  is,  no  doubt,  due  to  the  fact 
that  it  was  in  that  country  that  were  made  the  first  efforts 
to  manufacture  it  on  a  large  scale  in  Europe.  It  had  no 
monopoly  of  it,  for  it  was  not  long  before  manufactories  of 
it  were  to  be  found  scattered  in  many  European  countries. 
Factories  were  started  in  Germany,  France,  and  England 
not  very  far  behind.  Some  of  these  brands  of  white  lead 
soon  attained  a  high  degree  of  excellence,  and  have 
come  down  to  our  own  times,  their  names  being  still 
used  to  designate  some  very  fine  qualities,  —  such  as 
Cremnitz  white,  for  instance,  which  was  manufactured  in 
the  city  of  Crems  in  Germany.  Not  within  the  past 
hundred  years  has  there  been  any  white  lead  manu- 
factured there,  but  the  name  still  exists,  the  lead  usually 
sold  under  that  name  being  a  flake  white.  So  much,  then, 
for  good  quality;  for  tradition  still  preserves  it,  and  per- 
sists in  handing  a  name  down  to  us  more  than  a  century 
after  the  original  had  ceased  to  be  made. 

The  Dutch  Process 

The  "Dutch  process"  of  corrosion  has  been  handed 
down  to  us  with  but  few  changes  from  what  it  was  in 
its  primitive  days.  These  changes  consist  only  in  more 
sensible  labor-saving  devices  for  handling  the  various 
materials  used  in  the  manufacture  of  white  lead. 

Before  going  into  the  description  of  the  manufacture  of 
white  lead  by  the  "Dutch  process,"  it  will  be  best  under- 


WHITE  PIGMENTS  11 

stood  if  its  composition  be  well  studied;  therefore  the 
chemistry  of  white  lead  will  now  be  given. 

The  component  parts  of  white  lead  vary  somewhat  in 
the  several  specimens  of  it.  {  It  is  sometimes  erroneously 
called  a  carbonate  of  lead,  but  that  it  is  not;  at  least,  it  is 
not  a  pure  one.  If  it  was,  it  would  be  of  little  value  as  a 
pigment,  or  rather  its  value  would  be  greatly  lessened. 
Really,  it  is  a  combination  of  lead  carbonate  and  lead 
hydrate;  the  latter  is  what  gives  the  saponifying  and 
binding  properties.  This  hydrate  of  lead  should  be 
present  in  the  proportion  of  30  to  35  per  cent,  and  the 
carbonate  should  enter  the  combination  in  the  propor- 
tion of  65  to  70  per  cent.  Lead  hydrate  has  the  property 
of  counteracting  the  chalking  tendency  of  the  carbonate, 
but  it  has  the  drawback  of  rendering  white  lead  less 
opaque  or  more  transparent.  White  lead  should  there- 
fore in  round  numbers  have  two  thirds  of  its  weight  of 
carbonate  of  lead  and  one  third  of  it  the  hydrate.  Its 
formula  is  2PbCO3. 

The  usual  process  employed  in  the  manufacture  of 
white  lead  is  what  is  known  as  the  stack  system  of  the  so- 
called  Dutch  process,  which  name  in  reality  simply  stands 
for  the  chemical  process  producing  the  corrosion  of  the 
lead  metal  by  the  agency  of  dilute  acetic  acid  fumes, 
carbonic  acid,  hydrogen,  oxygen,  and  heat.  The  exact 
manner  of  conversion  of  the  metal  into  a  carbonate  is  very 
imperfectly  understood  even  at  this  late  day  by  chemists, 
who  in  their  conclusions  merely  guess  at  it  with  more  or 
less  plausibility  in  their  theories.  It  would  seem  that 
first  of  all  it  is  converted  into  an  acetate  of  lead,  but  as  it 
has  more  affinity  for  carbonic  acid  than  it  has  for  the 
acetic,  that  it  is  transformed  into  that.  As  to  the  "how  " 
and  "when,"  this  is  now  clouded  in  mystery,  and  it  still 
remains  for  some  one  to  satisfactorily  explain. 


12  MODERN  PIGMENTS 

Manufacture 

The  metallic  lead  used  in  the  manufacture  of  white 
lead  should  be  soft  and  free  from  antimony,  silver,  or 
any  other  impurity.  If  any  of  them  are  present  in  an 
appreciable  quantity  the  corroded  lead  will  not  be  so 
white  and  will  also  be  specky.  There  are  large  refining 
plants  in  the  United  States.  The  largest  in  the  world 
is  located  in  Newark,  N.J.,  where  metallic  lead  is 
desilvered  at  low  cost,  the  silver  obtained  usually  paying 
the  cost  of .  processing  it.  This  desilvered  metal  makes 
the  whitest  lead.  Spanish  lead  used  to  be  employed  by 
some  of  the  eastern  corroders,  but  what  with  the  duties, 
its  scarcity  and  increased  cost,  it  is  now  but  little  used. 
Some  is  employed  in  making  the  finer  qualities  of  flake 
white;  it  makes  a  dense,  and  therefore  more  opaque, 
white  lead. 

The  pig  lead  —  the  large  and  heavy  bars  of  metallic 
lead  as  they  come  from  the  smelters  —  is  melted  into  what 
in  corroder's  parlance  are  called  buckles.  These  buckles 
are  thin,  perforated,  circular  plates  of  lead,  and  are  about 
one-sixteenth  of  an  inch  thick.  The  disk-like  buckles  are 
placed  in  porous  clay  jars.  These  jars  have  projecting 
knobs  on  the  inside  upon  which  the  buckles  rest.  These 
projections  serve  the  purpose  of  separating  the  buckles 
from  each  other  in  the  jar.  This  allows  a  circulation  of 
air,  heat  and  of  the  gaseous  attacks  of  acetic  acid  vapor 
reaching  every  part  of  the  buckles,  as  it  can  ascend  from 
one  to  the  other  through  the  perforations.  There  is  also 
a  large  space  left  empty  at  the  bottom  of  the  jar  into  which 
is  poured  dilute  acetic  acid  of  the  strength  of  vinegar.  As 
vinegar  owes  what  value  it  has  as  a  corroding  agent 
to  the  acetic  acid  it  contains,  one  can  readily  see  that  the 
claim  made  by  some  corroders  that  they  use  actual 


WHITE  PIGMENTS  13 

vinegar  instead  of  dilute  acetic  acid,  and  making  for  this 
a  point  of  superiority,  is  all  "  bosh."  It  is  very  doubtful 
if  any  corroder  actually  uses  the  vinegar  of  commerce, 
notwithstanding  the  claims  made. 

After  the  jars  have  been  filled  with  buckles  to  nearly 
the  tops,  they  are  put  into  the  "  stack."  To  be  more 
accurate,  the  jars  are  placed  upon  the  floor  of  the  stack 
in  rows,  and  are  filled  from  a  large  box  containing  buckles 
of  lead  which  come  from  the  melting  room  and  shaping 
machine,  and  placed  there  in  these  boxes,  which  are 
carried  to  the  corroding  stack  houses  on  an  overhead 
railway  which  takes  them  wherever  wanted,  and  from 
which  they  can  be  raised  and  lowered  at  will.  After  all 
the  jars  in  the  tier  have  been  filled,  the  dilute  acetic  acid 
is  fed  to  each  jar  from  a  hose  in  short  order. 

The  stacks  themselves  are  compartments  inside  the 
corroding  houses.  They  are  boarded  up,  and  extend 
from  the  ground  floor  to  the  upper  one,  which  is  the  work- 
ing floor.  The  diagram  will  give  an  idea  of  the  arrange- 
ment. The  corroding  buildings  may  be  of  any  length 
with  any  number  or  size  of  stacks  inside  of  them.  Many 
of  the  big  corroding  plants  have  a  number  of  corroding 
houses.  Some  of  the  stacks  inside  of  the  same  building 
may  be  idle  or  in  many  of  the  different  stages  of  corrosion, 
each  stack  being  independent  of  the  one  next  to  it.  Thus 
one  can  see  in  the  same  corroding  house,  one  or  more 
stacks  being  filled  up  with  buckles  and  jars,  others 
engaged  in  the  corrosion  process,  while  others  again  are 
being  emptied  and  cleaned  out.  It  was  stated  that  the 
corroding  agent  was  dilute  acetic  acid  of  the  strength  of 
vinegar,  but  that  without  heat  would  produce  an  acetate 
of  lead  only.  So  heat  must  be  generated  and  carbonic 
acid  must  be  developed.  To  produce  both  of  these,  the 
corroder  uses  spent  tan  bark,  stable  manure,  or  a  com- 


14  MODERN  PIGMENTS 

bination  of  both.  Most  people  have  seen  how  the  market 
gardeners  generate  heat  in  their  hot-beds  in  the  coldest 
weather  by  using  stable  manure;  the  process  is  the  same 
that  the  corroder  employs.  A  layer  of  this  material  is 
first  placed  upon  the  ground  floor  of  the  stack,  and 
leveled  up,  and  a  layer  of  jars  placed  upon  it.  Upon  the 
jars  a  layer  of  boards  is  placed  to  keep  out  the  next 
layer  of  manure  which  is  placed  upon  the  boards,  then 
another  of  jars,  then  of  boards,  then  of  manure  again, 
and  this  is  repeated  over  and  o.ver  until  the  stack  has  been 
filled  nearly  to  the  level  of  the  working  alley  above. 

Each  one  of  the  layers  in  the  stack  has  a  chimney  of 
its  own.  This  chimney  consists  of  four  boards  nailed 
together,  and  reaches  to  the  top  of  the  stack  and  acts  as 
an  indicator  to  what  is  going  on  at  each  tier.  The  chim- 
neys are  kept  open  or  shut  according  to  requirements. 

The  heat  generated  by  the  tan  bark  and  manure 
vaporizes  the  acetic  acid  in  the  jars,  and  then  the  process 
of  corrosion  goes  on  until  all  the  acid  has  been  evaporated 
and  all  the  heat  has  been  spent.  It  usually  takes  from 
75  to  90  days  to  accomplish  this,  and  when  it  has  ex- 
hausted itself  the  layers  are  ready  to  take  down.  During 
the  generation  of  heat,  carbonic  acid  is  produced,  and  it 
is  from  this  source  that  it  is  supplied  to  the  lead. 

The  pots  when  taken  down  are  emptied  into  large 
revolving  cylinders  which  separate  the  white  lead  from 
any  that  remains  uncorroded.  The  white  lead  is  after- 
wards washed  through  several  waters  to  free  it  from  any 
acetate  of  lead  or  from  free  acetic  acid  that  may  be  pres- 
ent with  it.  Acetate  of  lead  is  entirely  soluble  in  water, 
and  can  thus  be  readily  gotten  rid  of. 

The  lead  is  then  ground  in  water  to  free  it  still  further 
from  any  acetate  remaining,  and  finally  filtered  through 
a  fine  silk  cloth  which  catches  any  specks  of  tan  or 


WHITE  PIGMENTS  15 

manure  that  may  have  found  their  way  into  the  pots  and 
that  the  numerous  washings  of  the  lead  have  not  removed. 

The  white  lead  is  now  run  into  large  vats,  where  it  is 
allowed  to  settle.  The  "pulp/'  as  the  mass  of  settled 
lead  is  called,  is  taken  to  the  drying  pans,  which  are  in  a 
separate  chamber  built  for  that  purpose.  This  chamber 
is  fitted  with  steam  pipes  all  around  it,  so  that  a  very  hot 
atmosphere  can  be  maintained  until  the  lead  in  the  pans 
—  as  the  large,  low  vats  are  called  into  which  the  pulp  is 
placed  —  is  bone  dry.  •' 

The  lead  is  then  crushed,  and  it  is  ready  to  sell,  either 
as  dry  lead  for  grinding  with  oil  as  white  lead,  or  for 
pottery  use  and  the  making  of  queensware  and  some 
varieties  of  chinaware.  Lead  ground  in  oil  is  the  only 
form  in  which  the  painters  usually  see  it. 

To  grind  white  lead  in  oil,  the  dry  lead  is  first  mixed 
with  the  quantity  of  linseed  oil  necessary  to  grind  it, 
say  about  nine  pounds  and  a  half  of  oil  to  the  hundred- 
weight of  dry  lead.  It  is  first  triturated  in  revolving 
mixers,  from  which  it  is  carried  mechanically  to  the 
grinding  mills  proper,  where  it  is  ground  either  double  or 
single.  The  double  mills  pass  the  lead  from  the  first  to 
the  second  without  manual  labor. 

The  speed  at  which  the  mills  are  made  to  revolve 
during  the  grinding,  and  the  lesser  or  greater  amount  of 
heat  developed  consequently  by  that  speed,  make  the 
ground  lead  paste  either  tough  and  stringy  in  texture,  or 
else  short  and  soft.  The  white  lead  itself  has  nothing 
to  do  with  it,  as  many  erroneously  suppose.  From  the 
same  batch  of  dry  lead,  the  grinder  can  turn  out  either 
kind  or  any  intermediary  degree  between  the  two  extremes 
simply  by  adjusting  the  speed  of  his  mills. 

White  lead  after  grinding  undergoes  some  mechanical 
change  in  its  atoms,  but  the  change  is  not  a  chemical 


16  MODERN  PIGMENTS 

one.  It  should  be  perfectly  cooled  before  it  is  packaged. 
Many  manufacturers  put  it  in  large,  tank-like  kettles, 
which  are  surrounded  with  water.  This  makes  the  lead 
more  unctuous,  and  gives  it  better  working  qualities. 
Lead  so  cooled  will  not  harden  in  the  packages,  which 
sometimes  happens  when  it  is  run  directly  from  the 
grinding  mills  into  them. 

It  was  stated  in  the  previous  paragraph  that  lead 
acquires  smoothness  and  better  working  qualities  when 
it  has  been  properly  ripened  in  large  masses  before  pack- 
ing. Few  manufacturers  give  it  time  enough  for  the 
process  to  become  completed;  all  are  in  a  hurry  to  turn 
over  the  product  into  money,  and  four  to  six  months' 
extra  waiting  is  hard  on  them  after  all  the  time  which 
has  been  required  since  the  pig  lead  was  melted. 

There  is  another  system  of  grinding  white  lead,  which 
is  known  as  the  "Pulp  Process."  The  manufacturers  call 
it,  pulp  ground,  but  in  reality  the  lead  is  not  ground  at 
all  —  that  is,  it  receives  no  other  grinding  than  that  which 
it  received  when  it  was  ground  with  water  previous  to  its 
becoming  pulp.  In  that  condition  it  is  certainly  finer 
than  it  is  possible  —  or  rather  practicable  —  to  grind  the 
crushed  bone-dry  lead  in  linseed  oil  by  many  repeated 
grindings  in  the  mills. 

The  wet  "pulped  "  lead  is  run  through  presses  by  some; 
but  nearly  all  manufacturers  who  make  a  "pulp  ground" 
lead,  withdraw  the  pulp  as  soon  as  it  has  settled  down 
from  the  water,  and  take  it  direct  to  a  "  chaser." 

A  chaser  is  a  circular,  low-sided  vat,  in  which  revolves 
a  heavy  roller.  This  roller  crushes  and  mixes  liquids  and 
solids  together  into  an  homogeneous  mass.  Chasers  are 
used  in  preparing  putty,  etc. 

White  lead  has  a  great  affinity  for  linseed  oil ;  for  water 
it  has  none  at  all.  The  pulped  lead  having  been  placed 


WHITE  PIGMENTS  17 

in  the  chaser,  linseed  oil  is  poured  on  it  and  the  machinery 
is  set  to  work;  the  lead,  having  more  affinity  for  the  oil, 
absorbs  it,  and  the  water  is  squeezed  out  by  the  weighty 
roller,  a  way  of  escape  being  provided  for  it,  and  in  a 
short  time  it  becomes  displaced  by  the  linseed  oil  which 
has  been  absorbed  in  its  stead. 

There  is  no  question  about  the  fineness  of  pulp  lead 
if  it  has  been  properly  ground  before  pulping  it,  nor  can 
there  be  any  about  its  whiteness.  Many  have  consider- 
able doubts  about  the  possibility  of  extracting  all  the 
water  out  of  the  lead.  Some  well-posted  men  claim  that 
three  to  five  per  cent  of  it  remain;  others  again  put  these 
figures  still  higher. 

Practical  painters  who  have  used  pulp-ground  lead 
for  years  say  that  it  has  acted  no  better  nor  no  worse  than 
other  leads  ground  in  the  usual  way.  All,  however,  are 
not  a  unit  in  this  testimony,  and  some  claim  that  it 
chalks  more  readily.  A  person  will  be  on  the  safe  side  if 
slow  in  adopting  its  use  exclusively,  but  should  proceed 
slowly  in  coming  to  a  conclusion.  By  using  it  side  by 
side  with  the  old  kinds,  and  noting  its  action,  in  time 
he  may  decide  for  or  against  its  adoption.  All  things 
being  equal,  pulped  lead  has  some  good  points  in  its 
favor,~  but  time  only,  and  lots  of  it,  will  decide  its  universal 
adoption. 

There  seem  to  be  very  little  and  surely  no  material 
differences  in  the  methods  of  corroding  lead  used  by  the 
lead  manufacturers,  excepting  possibly  that  some  few 
have  more  mechanical  labor-saving  devices  than  the  rest. 
Few  improvements  have  been  made  other  than  those 
mentioned,  and  those  mainly  since  the  introduction  of 
steam  and  other  motive  powers  which  have  replaced 
animal  and  human  energy  wherever  it  was  found  practi- 
cable. 


18  MODERN  PIGMENTS 

To  sum  up  the  Dutch  process  of  corroding  white  lead 
in  as  few  words  as  possible,  it  amounts  to  this:  It  is  the 
corrosion  of  metallic  lead  by  aid  of  acetic  acid,  carbonic 
acid,  oxygen,  and  hydrogen. 

When  it  was  said  in  preceding  paragraphs  that  there 
have  been  no  improvements  to  speak  of  in  the  manu- 
facture of  lead  by  the  Dutch  process,  this  was  meant  in  so 
far  as  the  original  application  of  the  principle  and  of  the 
system  carried "  on  by  the  Dutch  and  other  European 
corroders  of  the  long  ago,  —  the  stack  method. 

There  is  a  new  way  of  applying  the  same  principles  and 
agents  of  corrosion  used  in  the  Dutch  process.  Manu- 
facturers who  corrode  lead  in  the  new  way,  claim  that 
they  produce  a  white  lead  which  has  absolutely  the  same 
chemical  composition  as  that  produced  by  the  stack 
system,  that  its  atomic  formation  is  the  same,  that  its 
working  qualities  are  the  same  and  in  some  respects 
better,  —  in  short,  that  it  is  the  same. 

It  is  not  intended  to  pass  an  opinion  upon  the  claims 
made  by  these  gentlemen,  nor  to  certify  to  their  verity. 
What  is  here  said  must  not  be  construed  into  an  unquali- 
fied indorsement  of  them.  They  have  some  strong 
cards  in  their  hands,  and  they  seem  to  understand  how 
to  play  them.  That  their  system  of  corrosion  saves 
much  time  and  many  manipulations,  cannot  be  gainsaid; 
that  it  appeals  to  the  intellect  as  being  more  progressive 
than  the  other,  is  also  true.  It  gives  the  manufacturers  a 
more  perfect  control  of  the  action  of  the  corroding 
agents  in  the  process  of  corrosion,  thus  placing  them  in 
a  position  to  make  more  uniform  products. 

Several  manufacturers  representing  millions  of  capital 
have  been  corroding  by  the  cylinder  system  for  the  past 
twenty -five  years;  others  are  adopting  it  in  America  and 
European  countries.  In  the  United  States  some  two  or 


WHITE  PIGMENTS  19 

three  factories  using  that  system  have  a  very  large  out- 
put. The  practical  men,  the  painters  who  use  it,  are 
seemingly  well  satisfied,  so  it  looks  very  much  as  if  the 
system  had  passed  out  of  the  experimental  stage  and  that 
it  was  going  to  remain  with  us. 

This  cylinder  method  is  very  simple  and  easily  under- 
stood. To  all  intents  and  purposes  other  than  the 
manner  of  making  the  white  lead  it  is  entitled  to  have 
its  product  called  "  Dutch  process  "  white  lead  as  well 
as  that  produced  by  the  stack  system  —  if  the 
proposition  laid  down  in  a  former  paragraph  be  the 
correct  one.  It  is  repeated  below  in  a  shorter  form: 
That  the  name  " Dutch  process"  stands  for  lead 
corroded  by  the  agency  of  acetic  and  carbonic  acids, 
oxygen  and  hydrogen. 

The  operations  for  the  corroding  of  lead  by  the  cylinder 
system  are  few.  In  the  first  place,  the  pig  lead  is  melted 
and  poured  in  a  stream  against  which  a  jet  of  steam  is 
made  to  play.  This  pulverizes  the  lead  into  fine,  sandlike 
particles.  This  lead  sand  is  placed  in  revolving  cylinders 
connected  with  generators  wherein  acetic  acid  and  car- 
bonic acid  gases  or  vapors  are  evolved,  and  hydrogen  and 
oxygen  supplied  to  the  cylinders  at  will,  the  supply 
being  regulated  so  that  correct  proportions  of  each  will 
be  available  during  the  period  of  corrosion. 

The  particles  of  lead  sand,  being  so  very  small,  are 
quickly  acted  upon  by  the  corroding  agents,  as  the  slowly 
revolving  cylinders  keep  this  fine  sand  in  constant  com- 
motion so  that  no  part  of  it  can  remain  unexposed  to  the 
direct  action  of  the  attacking  vapors,  the  particles  con- 
stantly changing  their  location  and  presenting  new 
faces  to  their  attacks.  Thus  in  a  few  days  is  accom- 
plished what  would  have  required  months  by  the  older 
system. 


20  MODERN  PIGMENTS 

The  cylinder  system  excels  the  stack  system  in  more 
ways  than  one.  The  corrosion  is  more  perfectly  done,  and 
there  remains  but  a  very  small  percentage  of  "  blue " 
lead  —  as  the  uncorroded  lead  is  called  —  compared 
with  the  other  system.  To  all  intents  and  purposes,  it 
might  be  called  a  complete  corrosion. 

As  most  of  the  condemnation  of  the  white  lead  produced 
by  the  cylinder  system  can  usually  be  traced  to  those 
financially  interested  in  the  white  lead  produced  by  the 
older  system,  one  should  take  such  statements  with  the 
allowance  of  a  grain  of  salt,  and  discount  them  to  their 
just  values. 

It  is  presumable  that  poor  lead  can  be  and  is  produced 
by  both  the  stack  or  cylinder  systems;  and  again,  that 
good  lead  can  be  made  by  both.  If  a  lead  is  perfectly 
white,  fine,  free  of  surplus  moisture  other  than  that  which 
chemically  belongs  to  it;  if  it  has  good  opacity  and 
excellent  working  qualities,  —  we  need  have  no  hesitation 
in  using  it  whether  it  has  been  made  by  one  or  the  other 
method. 

Properties  of  White  Lead 

White  lead  stands  head  and  shoulders  above  any  other 
white  pigment  —  in  so  far  as  opacity  or  covering  proper- 
ties are  concerned  —  when  ground  in  oil  or  japan.  Con- 
sequently it  is  used  more  than  any  of  the  others;  in  fact, 
much  more  than  all  the  others  put  together  several  times 
over.  Its  working  qualities  under  the  brush  are  superior 
to  any  others,  this  being  caused  by  the  white  lead  com- 
bining chemically  with  the  linseed  oil  and  forming  a 
linoleate  lead  soap  which  works  freely  and  smoothly 
under  the  brush,  enabling  the  painter  to  apply  it  evenly 
with  a  minimum  amount  of  labor. 


WHITE  PIGMENTS  21 

It  is  not  alone  useful  as  a  white  pigment  for  painting 
surfaces  in  its  own  or  self  color,  but  it  is  used  to  even  a 
larger  extent  as  a  base  upon  which  all  the  lighter  tints 
are  made  by  addition  of  coloring  matter. 

Were  it  not  for  a  few  defects,  white  lead  would  certainly 
be  the  ideal  white  pigment  instead  of  being  only  the  most 
useful  one.  It  has  already  been  hinted  that  a  lead  which 
contains  too  much  hydrate  of  lead  in  its  composition 
would  be  somewhat  deficient  in  opacity,  and  that  if  it 
contained  very  much  more  than  two  thirds  of  the  car- 
bonate it  would  be  likely  to  chalk  badly,  or  worse 
than  the  ordinary.  No  matter  what  the  proportions  of 
hydrate  and  carbonate  the  white  lead  may  have  in  its 
composition,  in  time  it  will  chalk  if  exposed  to  the  action 
of  the  elements. 

In  the  best  leads  the  process  of  disintegration  (for 
that  is  what  chalking  means)  commences  in  about  one 
or  two  years  after  its  application,  usually  in  an  inappre- 
ciative  manner,  and  continues  until  in  time  one  can  rub  it 
off  the  building  by  simply  passing  the  hand  over  it.  As 
stated,  this  chalking  is  very  gradual  and  hardly  notice- 
able at  first.  The  chalking  can  be  hastened  or  retarded 
somewhat  by  the  improper  or  proper  use  made  of  the 
binding  vehicle;  also  by  the  improper  or  proper  admixture 
of  other  pigments. 

White  lead  is  a  good  drier  of  linseed  oil,  and  requires 
but  a  very  small  admixture  of  artificial  driers  to  hasten 
its  drying;  and  out  of  doors,  excepting  in  cold  or  wet 
weather,  none  are  needed.  Driers  seem  to  kill  the  elasti- 
city of  linseed  oil,  and  to  hasten  its  decay,  so  that  when 
used  at  all  in  connection  with  white  lead,  it  should  be 
done  with  very  modest  doses. 

Only  raw  linseed  oil  should  be  used  with  white  lead  for 
outside  painting.  The  raw  oil  is  much  more  elastic  and 


22  MODERN  PIGMENTS 

penetrating  than  the  boiled,  nor  will  the  chalking  com- 
mence as  soon  when  it  has  been  employed  than  it  would 
otherwise. 

The  greater  the  quantity  of  raw  linseed  oil  that  can 
be  incorporated  with  the  lead  and  make  it  cover  fairly, 
the  longer  the  time  before  chalking  will  begin.  It  stands 
to  reason,  therefore,  that  as  a  small  proportion  of  volatile 
oils  should  be  used  in  outdoor  painting  in  addition  to 
raw  linseed  oil  as  will  accomplish  the  legitimate  end  in 
using  it  at  all,  i.e.,  of  rendering  the  paint  more  fluid  and 
of  making  it  set  more  quickly.  The  above  applies  with 
even  greater  force  to  the  last  or  finishing  coat,  where 
volatile  oils  should  be  dispensed  with  entirely  wherever 
possible  to  do  so.  It  is  somewhat  harder  work  to 
properly  spread  paint  so  mixed,  —  that  is  admitted, — 
but  it  can  be  done.  White  lead  seldom  chalks  upon 
inside  work  that  is  not  exposed  to  the  weather,  and  what 
has  just  been  said  is  not  applicable  to  indoor  painting. 

White  lead  is  injuriously  acted  upon  by  the  action  of 
sulphureted  hydrogen  vapors,  which  will  quickly  turn 
it  black.  That  gas  converts  it  into  the  black  sulphide  of 
lead.  This  will  sometimes  occur  m  a  single  night,  there- 
fore its  use  should  never  be  resorted  to  in  localities  where 
this  gas  is  likely  to  develop. 

There  is  one  grade  of  white  lead  which  is  best  known  as 
flake  white.  It  differs  in  no  wise  from  ordinary  lead 
excepting  in  that  it  is  a  selected  white  lead.  The  flakes 
which  drop  off  the  buckles  corroded  by  the  stack  system, 
have  given  it  the  name.  This  outer  covering  of  the 
buckles  is  superior  in  opacity  to  that  from  which  the 
flakes  fell  off  and  which  comes  next  to  the  core  or  uncor- 
roded  lead  that  is  more  imperfectly  corroded,  and  which 
in  ordinary  lead  is  averaged  with  the  flakes  and  forms  the 
white  lead  of  commerce.  Therefore  flake  white  desig- 


WHITE  PIGMENTS  23 

nates  a  quality  of  white  lead  of  superior  corrosion  and 
which  possesses  extra  good  body. 

The  same  objectionable  features  enumerated  as  apper- 
taining to  ordinary  white  lead,  apply  to  this  with  as 
much  force.  It  is  used  mainly  by  decorators  and  sign 
painters  for  striping  in  car  shops  and  carriage  factories, 
for  coaches,  buses  and  wagons,  —  in  fact,  wherever  an 
extra  good-bodied  lead  is  demanded. 

Every  nation  has  its  own  system  of  packaging,  grading 
qualities  and  marketing  white  lead,  therefore  one  will  not 
find  the  same  rules  nor  trade  customs  in  the  United  States 
as  prevail  in  the  United  Kingdom,  nor  upon  the  continent 
of  Europe. 

In  the  United  States  an  unwritten  law  has  developed 
which  says  that  upon  all  packages  on  the  label  of  which 
the  manufacturer's  name  is  placed  and  the  words 
"  Strictly  Pure"  are  used  —  that  the  contents  of  the 
package  are  free  of  any  adulterating  material  and 
contain  nothing  but  pure  white  lead  ground  in  pure 
linseed  oil. 

It  is,  however,  true  that  some  jobbers  mark  some  fake 
leads  as  strictly  pure,  which  are  far  from  being  so  and  which 
are  adulterated  to  the  bitter  end;  but  then,  they  withhold 
from  them  their  own  names  and  adopt  some  flaring  name 
or  label  which  misleads  no  one  aside  from  the  unsophisti- 
cated and  ruralists  who  wish  to  buy  pure  lead  at  half  its 
market  value. 

So  if  a  lead  package  put  up  in  the -United  States  bears 
no  corroder's  name  nor  the  legend  "  Strictly  Pure"  upon 
it,  one  may  take  an  oath  and  swear  that  its  contents  are 
adulterated.  He  can  do  so  without  ever  having  seen  an 
analysis  of  it,  and  without  the  least  fear  of  committing 
perjury.  None  such  is  pure.  It  is  an  adulterated  lead, 
or  what  is  known  as  a  compound  lead. 


24  MODERN  PIGMENTS 

It  is  not  within  the  province  of  this  treatise  to  enter 
into  an  endless  review  of  the  merits  or  demerits  of  com- 
pounded leads,  nor  of  the  superiority  and  better  wearing 
qualities  claimed  for  them  by  their  manufacturers  over 
that  of  the  strictly  pure. 

There  can  be  little  doubt,  that  proper  combinations  of 
other  pigments  with  white  lead  are  beneficial  for  many 
purposes.  The  painter  should  be  well  enough  posted  to 
do  this  compounding  himself  to  suit  the  particular  job 
upon  which  the  compound  is  to  be  used.  Certain  com- 
pounds or  combinations  of  pigments  are  better  adapted 
to  sundry  conditions  than  they  are  to  any  other;  and  no 
ready-prepared  compound,  even  when  honestly  made 
after  a  uniform  formula,  is  likely  to  meet  his  requirements 
fully  in  this  regard,  however  good  it  may  be  for  the  right 
place. 

A  man  well  posted  upon  the  various  qualities  and 
defects  of  the  white  pigments  should  be  able  to  pick  out 
the  proper  corrective  ones  to  combine  with  white  lead  to 
suit  any  job.  If  it  be  old,  open  or  spongy,  it  certainly  will 
require  to  be  treated  differently  from  a  surface  which  is 
close  or  non-absorbing. 

There  are,  no  doubt,  very  good  lead  compounds  upon 
the  market  which  will  give  desirable  results  for  painting 
under  certain  conditions  to  which  they  are  admirably 
adapted,  but  which  will  cause  some  trouble  and  always 
mortification  elsewhere.  As  a  rule,  there  is  no  real 
advantage  to  be  gained  from  their  use.  They  are  not 
as  economical  as  those  similar  in  composition  and  com- 
pounded at  the  shop  from  strictly  pure  white  lead  and 
other  correctives  bought  as  such. 

Barytes,  or  the  native  barium  sulphate  (heavy  spar), 
plays  an  important  function  as  an  adulterant  of  white 
lead ;  for  that  matter,  it  does  in  the  adulteration  of  nearly 


WHITE  PIGMENTS  25 

all  other  pigments.  But  it  is  preeminently  adapted  as 
a  makeweight  for  white  lead:  its  heavy  weight  comes 
nearest  of  any  other  to  that  of  white  lead.  Its  trans- 
parency, too,  in  oil  is  another  reason  why  that  substance 
is  so  well  adapted  for  the  purpose  of  its  or  any  pigment's 
adulteration,  because  it  will  not  discolor  them.  More 
will  be  said  regarding  barytes  under  its  proper  heading, 
and  the  reader  is  referred  there  for  the  particular  details 
and  characteristics  belonging  to  that  pigment.  The  one 
object  why  it  was  entered  into  here  is  because  it  was 
necessary  to  point  out  the  main  source  of  adulteration  in 
connection  with  the  "off  brands"  of  white  lead  as  are 
best  known  and  called  all  brands  of  lead  that  are  not 
strictly  pure.  Compound  leads  which  are  sold  as  such, 
are  not  included  in  the  "off  brands,"  but  are  known  in 
the  trade  as  "compounds." 

Compound  leads  are  not  necessarily  adulterated  leads, 
because  in  the  first  place  they  do  not  claim  to  be  strictly 
pure  lead.  They  are  legitimate  articles  of  commerce, 
and  stand  upon  their  own  merits.  Painters  buy  them 
with  a  full  knowledge  of  what  they  are,  and  from  having 
had  some  previous  experience  with  them,  which  in  some 
instances  has  been  well  paid  for. 

The  same  substances  which  may  be  used  in  a  legitimate 
way  in  a  compound  lead,  and  of  whose  presence  the  buyer 
is  well  aware,  may  be  and  are  rightly  called  adulterants 
when  combined  with  lead  which  the  purchaser  is  led  to 
suppose  is  pure  white  lead. 

For  this  reason,  gypsum,  china  clay,  carbonate 
of  lime,  or  even  the  sulphate  of  lead,  which  are  all 
used  in  the  adulteration  of  white  lead,  are  not  such 
when  the  purchaser  buys  a  compound  lead,  as  the 
attempt  is  not  made  to  parade  them  as  something  which 
they  are  not. 


26  MODERN  PIGMENTS 

LEAD   SULPHATE 

This  lead  salt  is  never  sold  under  that  name  in  the 
supply  stores.  It  is  only  within  a  comparatively  short 
time  that  it  has  come  to  be  talked  about  in  connection 
with  paint  or  mixtures  of  paint. 

It  is  a  by-product  of  several  industries,  and  until  lately 
it  has  had  but  little  commercial  value  other  than  that 
which  inherently  belongs  to  it,  as,  if  it  could  be 
reduced  to  its  metallic  form,  it  would  be  worth  the  price 
of  metallic  lead  less  the  cost  of  conversion,  which  is 
expensive. 

It  can  be  readily  made  by  simply  adding  sulphuric 
acid  to  the  solution  of  a  lead  salt;  then  it  becomes^ pre- 
cipitated as  a  white  powder  which  is  insoluble  in  water 
and  absolutely  so  in  alcohol. 

Its  insolubility  makes  it  non-poisonous.  If  it  pos- 
sessed a  good  body,  or,  in  other  Words,  had  it  more  opa- 
city, it  would  be  a  very,  desirable  pigment^  It  is  not  as 
pure  toned  a  white  when  ground  in  oil  as  is  white  lead. 
It  is  not  readily  affected  by  the  vapors  of  sulphureted 
hydrogen.  Its  chemical  formula  is  PbSO4. 

Sulphate  of  lead  is  never  used  alone  as  a  pigment,  but 
as  an  adjunct  to  some  brands  of  white  lead,  and  largely 
so  in  ready-mixed  paints.  Its  chief  use  in  paint  mate- 
rial manufacture  is  for  such  grinders  as  put  out  a  brand 
of  white  lead  which  they  mark  as  strictly  pure.  It 
enables  them  to  place  a  product  upon  the  market  for 
which  they  can  vouch  as  strictly  pure  lead,  but  is  no 
more  entitled  to  be  so  called  than  sugar  of  lead  would 
be.  When  sold  as  "strictly  pure"  lead,  sulphate  of  lead 
is  as  much  entitled  to  be  called  an  adulterant  as  barytes, 
other  substances  which  have  no  business  to  be 


WHITE  PIGMENTS  27 

It  is  used  advantageously  in  color  making  —  such  as  the 
lemon  or  canary  chrome  yellow  —  but  in  the  above  they 
are  really  the  result  of  the  use  of  sulphuric  acid  in 
the  making  of  the  color,  and  not  because  they  are  placed 
there. 

SUBLIMED  LEAD 

Sublimed  lead  is  a  certain  form  of  sulphate  of  lead 
which  is  obtained  by  sublimation  in  Southwestern  Mis- 
souri, and  to  which  much  of  what  was  said  of  sulphate 
of  lead  proper  does  not  apply.  While  it  is  still  somewhat 
deficient  in  opacity  as  compared  with  hydro-carbonate 
white  lead,  it  comes  next  to  it  in  that  respect,  and  is 
used  extensively  by  mixed-paint  manufacturers  in  pre- 
paring those  goods. 

It  is  basic  sulphate  of  lead;  contains  about  one  fifth 
of  lead  oxide  and  about  five  per  cent  of  zinc  oxide  —  the 
ores  from  which  it  is  made  containing  zinc  in  combination 
with  the  lead.  It  is  sublimed  in  a  manner  somewhat 
similar  to  that  described  under  tne  heading  of  Zinc  White. 

One  property  entitling  it  to  consideration  is  its  non- 
poisonous  character.  Another  good  point  is  that  being 
an  oxysulphate  of  lead  it  is  not  subject  to  turning  black 
by  sulphureted  hydrogen  gases,  and  is  so  extremely  fine 
that  it  does  not  settle  readily  in  an  oily  vehicle.  It  is 
also  very  white  when  mixed  in  oil,  which  cannot  be  said 
of  sulphate  of  lead. 

DAHL  PROCESS  WHITE  LEAD 

This  form  of  lead  pigment  is  obtained  by  precipitation. 
By  a  modified  method  of  manufacture,  it  is  much  superior 
to  the  product  obtained  originally.  In  this  modified 
process  it  is  first  reduced  to  a  downy  or  feathery  state, 
after  which  it  is  placed  in  stationary  tanks  where  it  is  sub- 


28  MODERN  PIGMENTS 

jected  to  the  action  of  dilute  acetic  acid  which  converts 
it  into  a  basic  acetate  of  lead.  The  solution  is  subjected 
to  the  action  of  a  stream  of  carbonic  acid,  which,  as  already 
said,  lead  having  more  affinity  for  it  than  it  has  for  acetic 
acid,  combines  with  it,  and  is  precipitated  in  the  form  of 
basic  carbonate  of  lead. 

It  differs  from  Dutch  and  similar  process  leads  in  that 
instead  of  being  crystalline  it  is  amorphous  in  its  par- 
ticles. It  therefore  does  not  possess  quite  so  much 
opacity,  but  is  a  greater  absorbent  of  linseed  oil.  Natu- 
rally from  its  amorphousness  it  is  very  fine,  and  runs 
uniform  in  composition.  It  is,  however,  too  soon  to  form 
a  decided  opinion  of  its  merits,  whatever  it  may  present 
theoretically. 

WHITE  OXIDE  OF  LEAD. 

Periodically  somebody  or  other  discovers  —  or  rather 
thinks  he  does  —  something  new  in  a  white  pigment  of 
lead  derivation  which  in  his  estimation  is  sure  to 
displace  the  hydrate  oxide  of  lead,  and  that  his  discovery 
is  sure  to  fill  the  "long  felt  want"  of  a  pigment  —  one 
that  is  white,  non-poisonous,  not  injured  by  noxious 
gases,  and  for  which  they  claim  a  string  of  virtues  too  good 
to  be  true  and  too  numerous  to  mention.  These  great 
discoverers  appear  as  regularly  as  the  seventeen-year 
locust,  and  the  wreckage  of  the  last  of  them  is  hardly 
cleared  away  before  somebody  else  turns  up  ready  to 
launch  out  a  new  venture  which  proves  similar  to  the 
ones  which  have  gone  before;  but  as  it  is  launched 
out  under  a  new  name,  it  takes  a  little  time  before  it  is 
recognized. 

It  seems  that  some  people  will  never  learn  that  oxides 
of  lead  all  have  the  property  of  solidifying  into  a  hard 


WHITE  PIGMENTS  29 

mass  inside  of  the  package  containing  them  in  the  shape 
of  a  ground  paste,  if  ground  with  linseed  oil.  Yet  one 
after  another  of  the  discoverers  seems  to  be  able  to  enlist 
men  with  capital  to  back  their  foolish  ventures,  and  men 
of  good  business  capacity  and  caution  in  other  respects 
try  to  accomplish  the  impossible  —  i.e.,  grinding  lead 
oxides  with  linseed  oil. 

The  white  oxide,  the  monoxide  (litharge),  the  bioxide 
(red  lead),  the  teroxide  (orange  mineral),  all  have  the 
same  peculiarity  of  solidifying  in  time  when  ground  in 
linseed  oil.  When  the  retailers  who  are  not  posted,  have 
keg  after  keg  returned  to  them  after  a  few  months  — 
with  occasionally  a  claim  for  damages  —  it  proves  to  be 
the  beginning  of  the  end  for  "  oxide  of  lead  "  in  that 
locality. 

Some  in  sheer  desperation  have  gone  so  far  as  to  grind 
it  in  soft  linseed  oil  soap,  as,  when  ground  in  that,  it 
remains  in  a  smooth,  soft  paste;  but,  as  one  could  readily 
expect,  it  is  soon  found  out  and  the  "  jig  is  up."  The 
history  of  defunct  concerns  in  this  connection  would  make 
good  reading  on  short-sightedness  for  the  rising  generation. 

There  have  been,  and  some  firms  are  to-day  trying, 
experiments  with  other  salts  and  forms  of  lead.  Time 
may  prove  some  of  value;  none  so  far  have  any  claim 
to  superiority  over  the  old  hydrate-carbonate.  All  as 
yet  have  so  many  defects  that  the  very  grave  ones 
admitted  as  belonging  to  white  lead  look  small  compared 
with  them. 

The  Blowpipe  Test 

Adulteration  in  white  lead  and  many  other  forms  of 
lead  is  readily  detected  by  the  use  of  the  blowpipe. 
This  simple  test  is  within  reach  of  every  paint  dealer  or 
painter.  It  is  simple  and  easily  made:  A  piece  of  soft 
charcoal,  such  as  is  made  from  willow,  to  lay  the  lead  upon, 


30  MODERN  PIGMENTS 

an  ordinary  candle  or  spirit  lamp,  and  a  blowpipe.  This 
is  simply  a  small  metal  tube  curved  at  the  end.  The* 
curved  end  has  a  very  small  aperture,  and  that  is  placed 
against  the  flame  of  the  candle  while  the  operator  blows 
in  the  other  end  of  it;  this  throws  a  stream  of  blue  flame 
from  the  candle  to  the  charcoal,  or  to  that  part  of  it 
rather  where  the  lead  is  laid  upon  it,  the  operator  holding 
the  piece  of  charcoal  in  his  left  hand.  The  blowing 
should  be  regular  and  steady,  and  in  a  minute  or  two 
at  most  the  oil  will  be  burned  out,  and  the  white  lead 
will  be  converted  into  a  blue  lead  globule. 

If  it  has  been  adulterated  with  lead  sulphate,  barytes 
or  whiting,  china  clay,  etc.,  the  lead  cannot  be  reduced 
to  a  metallic  state  by  any  amount  of  blowing.  There 
will  be  a  mass  of  dry  white,  yellowish  or  grayish  color 
according  to  the  adulterant,  but  no  lead  will  show  up. 
As  small  a  percentage  as  10  per  cent  of  adulteration 
mixed  with  the  lead  will  prevent  its  reducing;  as  no 
lead  is  ever  adulterated  with  such  a  small  percentage 
as .  that,  there  will  be  no  difficulty  in  finding  it  with  the 
blowpipe. 

If  the  adulterant  is  sulphate  of  lead,  it  can  be  found  by 
the  great  difficulty  of  its  reduction;  few  men  can  use  the 
blowpipe  steady  or  long  enough  so  to  reduce  it,  as  it 
takes  much  more  heat  to  do  so.  That  form  of  it  men- 
tioned as  sublimed  lead  is  practically  irreducible  by  the 
blowpipe;  it  takes  over  1200°  F.  So  one  may  look  with 
suspicion  upon  any  white  lead  that  does  not  readily 
reduce  in  two  minutes. 

One  can  form  a  good  idea  of  the  purity  of  lead  by  putting 
a  little  of  the  lead  paste  upon  a  sliver  of  pine  wood,  and 
burning  a  match  or  two  underneath  it.  If  it  is  pure,  little 
globules  of  metallic  lead  will  appear  in  the  paste,  which 
will  not  be  the  case  if  the  lead  is  impure. 


WHITE  PIGMENTS  31 

The  blowpipe  test  is  valuable  only  to  test  the  purity 
of  hyd-oxi-carbonate  of  lead  —  the  white  lead  of  com- 
merce. It  will  not  apply  to  many  of  the  white  salts  of 
that  metal,  as  some  fuse  only  at  extreme  temperatures 
or  by  the  use  of  fluxes  which  none  but  experienced  men 
can  conduct  successfully. 

The  present  tendency  in  some  quarters  to  recognize  as 
"  white  lead/'  in  a  commercial  way,  the  basic  sulphate 
of  lead  or  sublimed  lead  would  of  course  nullify  the  test; 
but  why,  if,  as  claimed,  oxy-sulphate  of  lead  is  superior 
to  Dutch  process  hyd-oxi-carbonate  —  the  standard  white 
lead  of  commerce  —  should  it  seek  to  shelter  itself  under 
the  name  adopted  for  an  entirely  different  pigment? 

Will  it  not  be  better  for  both  to  retain  their  present 
designations  which  have  a  definite  meaning,  and  if  sub- 
limed lead  proves  itself  the  superior,  it  should  be  entitled 
to  a  distinctive  name  by  which  purchasers  can  purchase 
it  with  a  certainty  that  it  has  not  been  adulterated  with 
Dutch  process  lead,  and  it  should  not  seek  to  shelter  itself 
under  its  time-honored  appellation? 

The  above  is  written  not  as  a  disparagement  or  as  an 
indorsement  of  one  or  the  other  forms  of  leads,  but  in 
hope  of  saving  the  white  lead  and  sublimed  lead  indus- 
tries from  future  confusion,  whereas  now  the  two  are 
distinctly  known  and  recognizable  under  their  commercial 
cognomen. 


CHAPTER  III 
WHITE  PIGMENTS  (Continued') 
ZINC  WHITE 
History 

V— / 

ZINC  WHITE  as  a  pigment  is  of  much  more  recent  origin 
than  that  of  white  lead,  and  does  not  date  back  much 
farther  than  threescore  and  ten  years.  It  was  known 
before  that,  and  it  had  been  used  in  water  colors  a  few 
years  previously.  As  an  oil  pigment,  however,  it  may  be 
called  a  recent  one.  It  would  in  all  likelihood  have  been 
used  for  years  before  it  was,  but  for  the  difficulty  en- 
countered in  making  it  dry  properly;  and  writers  in  the 
beginning  of  the  nineteenth  century  incidentally  mention 
the  probability  and  possibility  of  its  becoming  a  useful 
pigment.  However,  it  was  in  the  forties  that  it  was  first 
used  as  an  oil  paint  with  a  drying  oil  by  Leclaire  in  France. 
From  that  time  to  the  present,  its  use  has  steadily  grown 
and  extended. 

It  took  a  long  while  at  first  to  break  down  the  pre- 
judices then  existing  against  its  use,  and  which  even  now 
prevent  many  from  using  it.  So  the  advent  of  this  pig- 
ment to  popularity  has  been  slow.  It  has  had  a  hard 
time  to  establish  itself  firmly. 

Chemistry  and  Manufacture 

There  are  two  very  distinct  qualities  of  zinc  white. 
The  better  quality  is  known  to  the  trade  as  " French" 


WHITE  PIGMENTS  33 

zinc,  and  the  other  as  "  American"  zinc;  both  have  the 
same  chemical  composition, —  oxide  of  zinc. 

French  zinc  is  that  which  is  made  from  the  zinc  metal, 
while  American  zinc  so-called  is  made  directly  from  the 
zinc  ore.  It  will  be  seen  that  the  terms  used  to  designate 
these  two  qualities  are  more  arbitrary  than  strictly 
true  —  at  least,  such  is  the  fact  to-day.  It  does  not  do 
America  justice  to  call  the  poorer  zinc  after  it,  but,  as  we 
have  seen  in  the  case  of  Cremnitz  white,  names  stick.  No 
amount  of  reasoning  is  likely  to  change  it  any  more  than 
in  another  glaring  instance,  i.e.,  English  and  American 
Venetian  red. 

The  French  are  •  no  doubt  entitled  to  the  honor  of 
having  first  used  this  valuable  pigment;  also  of  having 
first  produced  it  in  a  commercial  way;  so  that  importers, 
brokers,  and  paint  manufacturers  gave  it  the  name,  and 
habit  still  forces  the  name  to  remain.  France  never  had 
a  monopoly  of  its  manufacture,  and  Belgium  produces 
one  of  the  most  esteemed  of  its  brands  —  the  "  Vielle 
Montagne"  zincs. 

Within  the  past  twenty  or  twenty-five  years,  works 
have  been  established  in  the  United  States  which  are 
producing  zinc  oxide  by  the  "French"  process  which  is 
certainly  equal  in  quality  to  that  made  in  any  country. 
It  is  sold  as  ''French  "  zinc,  and  the  grinders  pay  as  good 
a  price  for  it  as  for  that  which  is  imported. 

The  process  of  manufacturing  zinc  white  is  very  sim- 
ple. The  metal  is  vaporized  by  heat  in  retorts,  whence 
it  is  carried  to  a  chamber  where  the  vaporized  zinc  comes 
in  contact  with  air  containing  oxygen,  for  which 
element  it  has  a  great  affinity.  It  combines  with  the 
oxygen,  and  is  at  once  converted  into  an  oxide  of  zinc. 
This  oxide  of  zinc  is  gathered  into  a  series  of  sacks  or 
small  chambers  suspended  with  the  mouths  opening 


34  MODERN  PIGMENTS 

downward.  That  which  is  lightest  and  whitest  is 
deposited  farthest  from  the  point  of  entrance  of  the 
vapor;  the  heavier  is  also  the  darker  and  is  deposited 
nearest.  This  darkness  is  caused  by  impurities  con- 
sisting mainly  of  unconverted  metal,  which  prevent  the 
grading  of  the  zinc  white  as  first  quality. 

Zinc  oxide  made  thus  is  very  light  and  flocky, 
resembling  in  a  manner  snow  or  eiderdown.  It  is 
selected  and  graded  according  to  quality,  whiteness, 
etc.;  after  which  it  is  submitted  to  the  action  of 
powerful  compressing  machinery  under  intense  heat; 
then  it  becomes  the  article  of  commerce  known  as 
"Dry  Zinc  White." 

Vast  quantities  of  it  are  annually  consumed  in  that 
shape  for  distemper  work,  for  the  better  class  of  kalso- 
mining,  etc.;  either  alone  as  a  white,  or  in  combination 
with  whiting  or  gypsum  or  with  coloring  matter  in  the 
making  of  certain  tints. 

For  use  in  linseed  oil  painting,  it  is  ground  either  in  a 
strong  drying  oil  which  has  been  previously  treated  to 
discolor  it,  or  in  drying  poppy  seed  oil  for  the  finer  grades 
of  work. 

It  is  usually  packed  in  tin  cans  ranging  from  one  to 
twenty-five  pounds  each.  Both  the  French  and  the 
American  zincs  are  sold  in  two  qualities  according  to 
their  whiteness.  The  whitest  and  best  is  sold  as  Green 
Seal  zinc  white,  while  that  which  is  of  a  darker  shade  is 
sold  as  Red  Seal.  These  are  usually  found  in  the  output 
of  all  grinders  of  zinc,  and  they  have  come  to  be  under- 
stood as  meaning  first  and  second  quality.  They  are 
used  upon  all  grades  of  zinc  ground  in  linseed  oil  or  poppy 
seed  oil,  except  upon  the  very  lowest  and  cheapest  grades 
of  American  zincs,  which,  in  addition  to  being  of  poor 
zinc,  are  usually  adulterated. 


WHITE  PIGMENTS  35 

American  zinc  is  made  in  precisely  the  same  manner  as 
that  described  for  French  zinc,  with  the  exception  that 
instead  of  using  zinc  metal,  zinc  ore  is  employed  in  its 
place.  It  is  made  from  the  vaporization  of  the  ore,  the 
oxidation  being  the  same;  the  process  in  all  respects  being 
identical,  and  so  are  the  after  treatments. 

From  the  impurities  contained  in  the  ore,  one  may  well 
surmise  that  the  product  cannot  be  equal  in  either  white- 
ness or  quality  to  that  made  from  the  metal  itself.  Both 
systems  are  now  used  in  the  United  States,  but,  as  stated 
before,  it  is  only  in  recent  years  that  it  has  been  made 
here  from  the  metal. 

The  chemical  formula  of  zinc  white  is  ZnO.  It  is  the 
only  oxide  of  that  metal  and  the  only  one  of  its  many 
salts  that  is  of  any  use  as  pigment  to  the  painter. 

Tests  for  Purity 

The  purity  is  easily  tested.  If  it  is  in  a  dry  powder, 
it  will  dissolve  readily  without  effervescence  in  either 
dilute  nitric  or  hydrochloric  acid. 

If  it  has  been  adulterated  with  barium  sulphate,  that 
substance  will  not  be  acted  upon  by  the  acids.  It  will 
be  left  undissolved  in  the  shape  of  a  white  powder  at  the 
bottom  of  the  dish.  If  there  is  effervescence  during  the 
dissolving  of  the  zinc  white  by  the  acids,  the  presence  of 
lime  in  the  shape  of  carbonate  of  lime  or  whiting  is  plainly 
indicated. 

If  the  zinc  to  be  tested  is  ground  in  oil  or  varnish,  it 
should  be  agitated  thoroughly  in  benzine  or  naphtha, 
which  will  dissolve  the  linseed  oil  out  of  it.  Let  it  rest 
and  deposit  after  the  agitation  has  been  thoroughly  done, 
then  pour  out  the  benzine  and  repeat  the  same  operation 
until  it  is  thoroughly  free  from  the  oil.  After  drying  the 
powder  —  which  will  be  done  quickly  if  left  in  the  open 


36  MODERN  PIGMENTS 

air  —  it  can  be  used  in  the  test  precisely  as  was  described 
for  the  dry  zinc  white. 

Zinc  white  is  not  affected  by  sulphureted  hydrogen 
gases,  nor  by  sulphurous  vapors  of  any  kind. 

Properties  and  Uses 

Oxide  of  zinc,  or  zinc  white  as  it  is  best  known  to  the 
paint  trade,  has  had  its  praises  sung  to  all  kinds  of  tunes 
in  every  civilized  country  where  paint  is  used.  It 
deserves  a  good  deal  of  this  admiration,  and  is  one  of  the 
most  valuable  additions  to  the  list  of  white  pigments,  and 
really  is  indispensable  in  the  well-regulated  paint  shop. 
It  should  be  used  as  a  component  part  in  many  a  mixture. 
But  much  of  the  praise  we  hear  should  be  carefully 
weighed  and  conclusions  slowly  reached.  It  will  hardly 
do  to  swallow  the  whole  of  the  flattery,  at  least  not  to  the 
extent  some  would  have  it,  that  of  discarding  the  old 
standby,  white  lead,  and  substituting  for  its  use  that 
of  zinc  white.  While  some  of  its  friends  are  extravagant 
and  unquestionably  go  too  far,  it  is  nevertheless  an 
excellent  pigment  in  its  proper  place.  When  judiciously 
used,  it  is  invaluable,  and  will  give  every  satisfaction.  If 
used,  as  it  sometimes  is,  in  a  haphazard,  hit-or-miss  sort 
of  way,  it  will  not  take  many  years  before  sorrow  will 
come  of  it,  and  the  painter's  reputation  goes  a-fishing. 

For  interior  work  in  either  distemper  or  enamel,  zinc 
white  is  greatly  to  be  preferred  to  any  other  white  pig- 
ment, and  its  praises  may  be  sung  in  a  very  high  pitch. 
Then  it  deserves  the  homage  of  every  painter  and 
decorator  in  the  land.  Its  freedom  from  the  attacks 
of  white  lead's  greatest  enemies  —  sulphurous  fumes  — 
compels  its  use  under  all  circumstances  where  these  are 
present. 


WHITE  PIGMENTS  37 

It  is  true  that  the  French  government  is  throwing  its 
influence  in  favor  of  the  use  of  zinc  and  discouraging  the 
use  of  white  lead,  and  has  passed  some  very  stringent 
legislation  in  regard  thereto.  Simmered  down  to  its  real 
value ,  this  means  that  journeymen  painters  in  that 
country,  either  through  bad  habits  or  careless  use  of 
white  lead,  are  more  subject  to  lead  poisoning  than  those 
of  other  nations.  These  have  circulated  petitions,  held 
mass  meetings,  and  have  forced  upon  the  attention  of  the 
government  what  they  choose  to  call  "  the  evils  of  white 
lead."  The  legislation  in  a  great  measure  is  the  result  of 
this  agitation.  True,  nothing  but  zinc  can  go  on  to  public 
buildings,  etc.  This  is  heralded  and  made  use  of  to  the 
limit,  by  those  most  interested  in  its  manufacture  and 
sale;  nevertheless,  when  all  the  facts  in  the  case  are  fear- 
lessly looked  into,  it  means  but  little. 

All  public  buildings,  and  nearly  all  others  of  any  sort, 
are  of  stone  in  France.  The  painting  is  principally  that 
of  the  interiors  and  some  of  the  doors  and  blinds,  which 
are  usually  painted  in  colors  and  not  with  zinc  on  the 
outside.  Some  few  are  painted  white,  or  in  tints  made 
from  white  zinc  as  a  base,  and  they  show  very  plainly  that 
had  the  government  been  as  careful  to  take  the  advice 
of  more  practical  men  instead  of  that  of  theorists,  and 
had  not  to  knuckle  under  the  goods  handled  by  the 
journeymen  who  are  voters,  and  their  friends  who  are 
voters  too,  there  would  be  less  cracked  paint  to  be 
burned  off  than  there  is  to-day  and  will  continue  to  be. 
It  is  only  a  question  of  time  when  the  practice  will  have 
to  be  abandoned,  as  the  French  are  no  greater  lovers  of 
eyesores  in  the  shape  of  paint  scales  than  any  other 
people. 

The  particles  or  atoms  of  zinc  white  have  a  great 
affinity  for  each  other.  As  has  been  already  related 


38  MODERN  PIGMENTS 

when  describing  the  manufacture  of  zinc  white,  the 
atoms  cling  together  like  snow  or  eiderdown  interweaving 
each  other,  and  that  they  are  compressed  by  powerful 
machinery.  This  adherence  and  brotherly  embracing  of 
each  other  in  these  atoms  is  remarkable,  and  stands  as  the 
very  opposite  of  that  of  the  atoms  of  white  lead,  which 
have  no  affinity  whatever  for  each  other.  This  in  part 
explains  why  lead  chalks  so  easily.  When  the  binding 
of  the  linseed  oil  which  holds  the  atoms  together 
begins  to  decay,  they  begin  also  to  drop  and  loosen 
from  each  other  —  they  fall  singly,  having  nothing  to 
hold  them. 

The  reverse  condition  takes  place  with  zinc  white.  Its 
atoms  have  such  an  affinity  for  each  other  that  they  hold 
together  in  a  solid  mass.  When  the  oil  has  so  decayed 
that  it  can  no  longer  bind  the  zinc  and  hold  it  against  the 
building,  the  paint  cracks  and  gradually  loosens  from 
it,  forming  a  scale  which  will  eventually  drop  away  in  a 
mass  in  the  same  way  and  manner  as  the  bark  does  from 
the  Buttonwood  or  sycamore  tree. 

While  the  use  of  zinc  white  alone  for  outside  painting 
is  not  to  be  recommended,  a  combination  of  it  in  proper 
proportions  with  white  lead  will  in  a  good  measure 
counteract  the  inherent  defects  appertaining  to  each. 
The  tenacity  of  the  zinc  white  will  retard  the  falling  away 
of  the  white  lead;  and  that,  in  return  for  the  good  deed 
done  it,  will  help  to  prevent  the  excessive  tenacity  of  the 
former. 

There  can  be  no  set  rule  formulated  giving  the  exact 
proportion  that  each  should  have  in  making  up  a  com- 
bination. Under  certain  conditions,  lead  paint  to  which 
25  per  cent  of  zinc  white  has  been  added  may  crack  and 
scale,  while  again  under  others  as  much  as  60  or  even  80 
per  cent  would  not  affect  it  injuriously. 


WHITE  PIGMENTS  39 

As  this  treatise  is  written  for  the  purpose  of  giving 
information  that  concerns  pigments,  and  not  upon  the 
application  of  paint,  details  therefore  which  properly 
belong  to  a  book  on  painting  cannot  fully  be  elucidated 
here.  Possibilities  are  indicated  to  show  what  the 
properties  of  the  pigments  are  and  how  to  correct  some 
of  their  bad  points.  Generally  speaking,  therefore,  a 
paint  for  ordinary  surfaces  should  not  contain  more  than 
20  to  25  per  cent  of  zinc  to  75  or  80  per  cent  of  white  lead 
for  outside  painting.  The  figures  given  are  conservative, 
and  circumstances  might  alter  them  considerably. 

The  non-drying  properties  of  zinc  white  have  already 
been  mentioned.  It  is  therefore  necessary  to  add  some 
driers  to  the  linseed  oil  used  in  its  application.  This  is 
especially  the  more  essential  if  raw  linseed  oil  be  used ;  and 
it  is  really  the  only  one  which  should  be  employed  in  con- 
nection with  zinc  white  for  outside  painting,  on  account  of 
its  greater  elasticity,  which  lessens  its  tendency  to  crack 
and  scale,  by  lengthening  the  period  until  decay  com- 
mences. 

For  distemper  painting,  aside  from  its  beautiful  white 
tone  when  used  alone,  or  the  clearness  of  the  tints  made 
from  it  and  the  addition  of  coloring  pigments,  it  has  also 
a  soft,  satin-like  finish  impossible  to  produce  with  whiting 
or  gypsum  whites.  Therein  lies  the  secret  of  many  a 
kalsominer,  whose  work  is  so  much  superior  to  that  of 
others  who  do  not  use  it  and  have  not  discovered  its  value. 
The  former  are  looked  for  and  kept  busy  while  the  latter 
are  looking  around  for  work.  The  clearness  of  tints  made 
with  zinc  is  not  confined  to  distemper  work,  but  is  still 
more  strikingly  noticeable  when  tints  are  made  from  pig- 
ments ground  in  oil,  and  zinc  white  in  oil  or  poppy-seed  oil. 


CHAPTER  IV 

WHITE  PIGMENTS  (Continued) 

THE  EARTH  WHITES 

General  Remarks 

EARTH  WHITES  are  so  named  to  distinguish  that  class 
of  white  pigments  which  owe  their  origin  to  mother  earth 
in  contradistinction  to  those  which  are  derived  from  a 
metallic  origin,  as  lead  and  zinc. 

None  of  the  earth  whites  are  as  valuable  to  the  work- 
man in  oil,  painting;  in  this  respect  they  are  entirely 
different  from  the  metallic  whites.  When  mixed  with 
linseed  oil,  they  assume  a  dirty,  dingy,  measly-looking 
white.  All  are  more  or  less  transparent,  or  at  best  are 
semi-transparent.  By  themselves  they  may  be  called 
useless  as  oil  paints,  but,  for  all  that,  some  are  very  useful 
when  employed  as  adjuncts  to  the  metallic  whites  in  oil. 
Their  usefulness  lies  chiefly  in  the  correction  of  some 
defects,  and  that  is  their  chief  use  in  connection  with  that 
vehicle. 

In  kalsomining  and  distemper  work  they  become  true 
pigments  in  every  sense  of  that  word.  They  impart  a 
color  of  their  own  to  the  other  pigments  with  which  they 
are  mixed.  In  water,  they  are  invaluable. 

Lime,  clay,  and  silica,  with  admixtures  of  other  sub- 
stances in  small  quantities,  form  the  basis  of  nearly  all 
the  earth  whites.  According  to  which  of  them  mainly 
enters  into  the  respective  compositions  and  predomi- 
nates, they  are  known  by  various  names. 

40 


WHITE  PIGMENTS  41 

Most  all  the  earth  whites  are  to  be  found  in  abundance 
in  many  parts  of  the  world.  Most  of  them  are  cheaply 
mined  and  prepared  for  use,  consequently  they  are  inex- 
pensive. This  cheapness  makes  them  very  attractive 
for  compounding  with  white  lead  or  zinc  white,  openly  so 
in  the  goods  known  as  compound  leads,  etc.,  or  secretly 
so  in  the  preparation  of  the  "off  "  brands.  The  greatest 
harm  that  any  of  them  do  in  either  the  off  brands  or  the 
compound  leads  is  that  they  reduce  the  covering  proper- 
ties in  these  in  nearly  the  same  ratio  as  the  quantities 
into  which  they  enter.  It  is  said  "  nearly,"  but  as  some  of 
these  earth  whites  are  semi-transparent  and  have  cover- 
ing properties  of  their  own,  it  is  true  therefore  in  the 
main  of  most  of  them.  Their  spreading  possibilities  are 
increased,  and  pound  for  pound  they  spread  farther  than 
lead,  so  that  a  greater  number  of  square  yards  can  be 
painted  with  a  given  weight.  This  is  due  to  the  fact 
that  they  absorb  more  linseed  oil  than  does  white  lead. 
This  makes  them  wear  longer,  and  helps  to  protect  the 
lead  in  the  combination.  Some  of  these  earth  whites 
have  strong  caustic  properties;  this  causticity  saponifies 
the  linseed  oil,  and  as  the  saponification  formed  is  a 
partially  soluble  one,  it  is  necessary  to  be  careful  of  their 
use. 

CARBONATE  OF  LIME,  OR  WHITING 
Chemistry  and  Source  of  Supply 

Carbonate  of  lime,  or  whiting  as  it  is  popularly  called, 
whose  chemical  formula  is  CaCO3,  is  plentifully  supplied  by 
nature  in  a  nearly  pure  state  in  the  shape  of  chalk.  It  is  at 
least  pure  enough  for  use  as  a  pigment  after  the  removal  of 
the  coarser  substances  mixed  with  it,  such  as  silica  and 
other  impurities,  by  levigation.  It  is  sometimes  made 


42  MODERN  PIGMENTS 

artificially  from  certain  varieties  of  limestone,  which  in 
the  United  States  is  more  abundant  than  chalk. 

The  principal  source  of  supply  is  chalk.  That  is  the 
natural  carbonate  of  lime.  All  it  needs  is  crushing  and 
afterward  levigating. 

Levigating  is  the  technical  name  used  to  designate  the 
operation  of  washing  out  the  impurities  present  in  all 
natural  earth  pigments.  Whenever  that  word  is  used 
in  this  treatise  in  subsequent  chapters,  one  will  under- 
stand that  it  is  employed  to  designate  the  washing  out  of 
impurities  consisting  of  heavy  sand,  pebbles,  roots,  etc. 

After  the  chalk  has  been  crushed  or  powdered,  this  is 
mixed  with  water  and  thoroughly  agitated,  that  it  may 
all  be  dissolved  and  held  in  suspension  by  the  water.  It 
is  then  run  off,  conducted  through  pipes  to  a  succession 
of  vats  where  the  liquid  mass  overflows  from  one  to  the 
next,  and  so  on.  The  finer  atoms  being  the  lightest 
they  are  held  in  suspension  the  longest,  and  they  flow 
to  the  farthest  vats  before  depositing,  the  sand  and  other 
heavy  impurities  settling  in  the  first  ones,  so  that  the 
quality  of  the  settlings  increases  or  decreases  according  to 
the  longer  or  shorter  distance  of  the  settling  vats  from  the 
first  of  these  where  the  outflow  starts. 

The  first,  second,  and  third  vats  contain  nearly  all  the 
worthless  substances,  which  are  usually  thrown  away. 
The  rest  are  graded  according  to  fineness.  The  pulp 
is  then  dried,  crushed  in  large  lumps  or  powdered,  packed 
in  barrels,  and  the  last  is  sold  as  "  Gilder's"  whiting- 
chalk  which  has  simply  been  crushed  and  powdered 
without  having  been  subjected  to  the  levigating  process 
is  known  by  the  name  of  "Commercial"  whiting. 

The  qualities  and  styles  of  packages  which  a  few  years 
ago  were  to  be  found  upon  the  market  under  various 
fancy  names  have  nearly  all  disappeared.  For  in- 


WHITE  PIGMENTS  43 

stance,  the  small  cones  of  Spanish  white,  the  brands 
of  Paris  white,  London  white,  etc.,  are  seldom  to  be  found. 

Some  decorators  prefer  what  is  known  now  as  "lump" 
whiting.  This  is  not  lump  chalk,  as  some  might  suppose 
it  to  be.  That  would  be  too  hard  to  dissolve,  —  in  fact,  it 
would  not  dissolve;  besides,  the  impurities  lump  chalk  con- 
tains would  bar  it  from  use  by  that  class  of  workmen. 
Good  lump  whiting  is  the  same  as  the  best  grade  of 
gilder's  whiting,  with  the  only  difference  that  after  the 
levigated  pulp  is  dry,  instead  of  being  powdered  it  is 
simply  broken  up  into  chunks  for  the  handy  packing 
of  it  in  barrels. 

That  it  is  better  than  the  corresponding  quality  that 
has  been  powdered,  is  claimed  by  some  decorators.  It  is 
a  question  requiring  a  Philadelphia  lawyer  to  decide.  It 
is  too  hard  for  the  ordinary  mortal  to  answer.  It  is  a  rem- 
nant of  the  times  when  the  old  bosses  used  the  dabs  of 
Spanish  white,  which  were  just  pulp  dipped  out  and  dried 
in  cone-like  shapes,  and  were  in  those  days  known  to 
every  painter  in  the  land.  But  to-day,  with  powerful 
machinery  to  crush  the  whiting,  and  if  this  has  been  well 
levigated,  it  looks  as  if  the  powdered  whiting  had  the 
best  end  of  the  arrangement.  It  dissolves  in  water  more 
readily  than  the  lump,  therefore  is  more  desirable  for 
the  painter's  use,  because  it  saves  his  time. 

Properties  and  Uses 

Whiting  is  a  very  good  distemper  pigment,  and  is 
probably  more  extensively  used  than  any  of  the  white 
earth  pigments.  It  is  used  chiefly  by  kalsominers,  deco- 
rators in  distemper  painting,  and  in  immense  quantities 
by  the  wall-paper  manufacturers  in  preparing  their  print- 
ing tints. 


44  MODERN  PIGMENTS 

In  linseed  oil  it  is  very  indifferent,  to  say  the  least. 
From  its  causticity,  it  must  be  very  active  in  saponifying 
and  destroying  the  linseed  oil.  It  never  dries  very  hard 
with  it,  and  where  the  oil  has  been  applied  thick,  it  will 
skin  over  the  soft  stuff  underneath  and  will  come  off  with 
but  little  provocation.  It  always  imparts  a  dull,  dirty 
tone  to  any  tints  made  by  adding  coloring  matter  to  it, 
or  to  white  lead  compounds  where  it  predominates.  For 
employment  alone,  its  transparency  is  against  it.  Small 
quantities  of  it  added  to  the  megilp  used  by  grainers 
will  make  the  color  comb  better  and  permit  it  to  be  put 
on  heavier,  and  still  be  more  transparent  than  would  be 
possible  without  it. 

There  are  several  cretaceous  earths  which  at  times  have 
been  used  as  paint  or  adjuncts  to  white  lead,  but  none  of 
them  have  proved  very  satisfactory.  Their  use  is  now 
obsolete.  Far  better  substances  can  be  had  which  are 
fully  as  cheap  as  whiting.  The  chief  use  of  whiting  is 
in  water-color  painting,  and  in  this  connection  it  is  con- 
sumed in  enormous  quantities.  The  wall-paper  printing 
industry  uses  it  in  the  preparation  of  its  tints.  The 
kalsominers  and  fresco  painters  also  are  large  consumers. 
The  putty  manufacturers  also  employ  it  in  the  prepara- 
tion of  that  article. 

rv 
CHINA  CLAY,  OR  KAOLIN 

China  clay  is  the  only  white  earth  pigment  that  has 
any  body  in  oil,  but  even  the  best  samples  could  hardly 
be  called  semi-transparent.  This  class  of  white  earth  is 
also  known  under  the  general  names  of  argillaceous  and 
clay  white.  It  varies  greatly. 

Properties  and  Uses 

The  kaolin,  or  china  clay  of  commerce,  is  the  best  repre- 
sentative of  the  class.  It  is  nearly  a  pure  clay,  and  that 


WHITE  PIGMENTS  45 

is  why  it  is  better  bodied  than  the  cretaceous  or  silicious 
earths.  It  is  very  much  better  than  whiting  as  a  com- 
ponent part  of  off  leads  and  lead  compounds.  Never- 
theless it  is  far  from  being  an  ideal  substance;  it  has 
some  grave  defects  of  its  own,  but  it  has  a  better  body, 
and  is  not  an  active  destroyer  of  linseed  oil. 

Its  defects  are  that  it  dulls  the  tone  of  white  lead,  and 
that  it  muddies  that  of  tints  in  about  the  same  manner 
and  for  similar  reasons  as  whiting  does. 

It  is  also  useful  as  a  distemper  color,  working  nicely 
under  the  brush;  but  as  it  does  not  make  as  smooth  a 
job  as  whiting,  it  is  therefore  very  seldom  employed  for 
that  class  of  work. 

Its  chief  use  is  that  of  an  extender,  as  an  adulterant 
in  off  leads  or  compounds,  ochers  ground  in  oil,  Venetian 
reds,  etc.  Its  greater  body,  heavier  weight,  and  being 
much  less  caustic  than  carbonate  of  lime,  render  it  much 
better  adapted  for  purposes  where  these  qualities  count. 

But  in  common  with  all  earth  pigments  which  contain 
a  large  proportion  of  clay  or  alumina  in  their  composi- 
tion, the  great  trouble  is  that  clay  has  the  property  of 
absorbing  water  and  of  parting  with  it  readily.  This 
hygroscopic  property  is  lessened  when  mixed  with  oil, 
but  not  altogether  eliminated.  After  the  oil  has 
thoroughly  dried,  and  from  exposure  and  decay  become 
porous,  clay  pigments  absorb  water  from  the  atmosphere, 
and  when  the  heat  of  summer  comes,  this  moisture  is 
given  out.  This  is  the  main  reason  why  so  much  trouble 
has  been  reported  from  the  use  of  ochers.  There  is  no 
doubt  that  in  the  majority  of  cases,  this  was  due  to  the 
use  of  an  ocher  which  contained  a  very  large  percentage 
of  alumina  in  its  base. 

This  constant  absorbing  or  parting  with  moisture  is 
bound  to  produce  blistering,  and  later  on  scaling,  and  is 


46  MODERN  PIGMENTS 

the  principal  cause  of  mildew.  It  also  causes  the  sinking 
in  of  colors,  which  means  a  cloudy,  fady,  muddy,  uneven- 
looking  surface. 

GYPSUM  (SULPHATE  OF  LIME) 
History  and  Provenance 

Gypsum  is  plentifully  found  in  the  natural  state  —  a 
soft  rock  —  in  nearly  all  parts  of  the  globe.  It  is  known 
to  every  one  in  its  calcined  condition  under  the  form 
and  name  of  plaster  of  paris.  In  this  form,  however,  it 
is  of  little  use  as  a  pigment.  It  is  therefore  chiefly  in 
its  uncalcined  condition  that  it  will  be  considered. 

It  is  first  levigated  and  freed  from  impurities  in  much 
the  same  manner  as  has  been  related  was  used  to  clean 
chalk  from  its  impurities.  It  is  chiefly  in  this  condition, 
after  thorough  drying,  that  it  is  useful  either  as  an  adjunct 
to  other  pigments,  or  as  the  principal  ingredient  in  all  the 
so-called  anticalcimine,  gypsine,  etc.,  —  the  prepared  dis- 
temper paints  whose  manufacturing  headquarters  are 
located  in  Grand  Rapids,  which  is  situated  in  the  heart 
of  the  gypsum  beds  of  Michigan. 

Properties  and  Uses 

For  distemper  purposes  and  water  colors,  gypsum  is 
well  fitted,  although  it  does  not  work  as  smoothly  as 
whiting,  nor  does  it  make  as  solid  a  covering.  In  some 
other  respects  it  is  superior  to  it;  it  has  much  better 
tenacity  and  adhering  properties.  It  is  better  to  buy 
it  ready  prepared  for  application.  It  requires  a  long 
experience  in  its  preparation.  This  the  manufacturers 
possess;  and  experimenting  continually,  they  have  been 
able  to  correct  some  of  its  faults  and  to  put  out  a  line  of 


WHITE  PIGMENTS  47 

goods  which  is  much  better  than  any  thing  the  painter 
could  possibly  prepare  for  himself. 

In  relief  work  gypsum  is  the  principal  substance  used 
in  the  mixtures. 

It  is  also  useful  in  oil,  not  so  much  as  a  pigment  as  an 
adjunct;  as  a  corrector  or  betterer,  if  it  maybe  so  called. 

It  has  some  of  the  defects  of  other  earth  whites,  the 
main  one  being  its  transparency.  It  possesses  no  opa- 
city in  oil,  or  next  door  to  none.  When  used  excessively 
it  dulls  tints  the  same  as  the  rest  of  them.  Unlike  many, 
it  has  no  causticity,  so  that  it  does  not  injuriously  affect 
linseed  or  any  other  of  the  fixed  oils.  Therefore  when 
used  judiciously  with  white  lead,  it  will  retard  its  chalk- 
ing, for  it  is  a  good  absorbent  of  oil,  and  is  inert.  But 
it  must  be  used  in  reason,  or  it  will  make  the  white  lead 
look  off-color  and  too  transparent. 

It  is  also  used  by  color  makers  as  a  base  for  certain 
colors,  but  of  that  more  will  be  said  as  occasion  will 
require  under  the  proper  heading.  It  is  chiefly  in  that 
connection  that  its  usefulness  lies. 

Chemistry 

Sulphate  of  lime  when  calcined  at  a  heat  of  110°C. 
loses  its  water  of  hydration  and  forms  the  well-known 
article  of  commerce,  plaster  of  paris. 

In  that  condition  it  absorbs  water  readily  and  recom- 
bines  with  it,  returning  to  its  hydrate  or  natural  condi- 
tion. This  renders  it  unfit  for  use  as  a  pigment,  as  it 
would  harden  when  mixed  with  the  water  used  to  thin  it 
in  distemper  work,  and  would  absorb  enough  moisture 
from  linseed  oil,  which  contains  a  small  percentage,  and 
from  the  atmosphere,  which  at  times  is  heavily  charged 
with  it,  to  harden  even  when  ground  in  oil.  When  it 
has  become  heated  to  500°  C.  then  it  loses  the  power  of 


48  MODERN  PIGMENTS 

absorbing  moisture,  and  it  is  in  that  condition  that  it  has 
to  be  for  the  purposes  of  the  manufacturer  of  pigments. 

It  is  never  found  in  that  shape  in  a  commercial  way, 
and  for  that  reason  the  painter  cannot  avail  himself  of 
its  use  in  order  to  compound  it  with  other  pigments. 

Should  the  future  demand  for  gypsum  of  500°  C.  be 
found  to  grow,  it  is  highly  probable  that  manufacturers 
will  grind  it  in  oil.  At  the  present  it  is  known  only  to 
few  aside  from  the  color  makers,  so  there  is  no  market 
demand  for  it.  Probably  the  reason  is  that  it  is  a  very 
hard  substance  to  grind  after  such  high  calcination. 
When  it  enters  in  combination  with  other  pigments  it  is 
much  easier  ground,  and  it  is  always  in  that  shape  that 
it  is  ground. 

SILICATE  EARTHS  (SILVER  WHITE) 
Properties  and  Uses 

Silver  white  is  known  to  most  painters,  probably  not 
as  a  paint  or  pigment,  but  as  an  ingredient  entering  into 
the  preparation  of  fillers. 

It  is  hardly  worthy  to  be  called  a  pigment,  as,  even  when 
mixed  with  water  for  distemper  work,  it  shows  but  little 
opacity,  and  is  very  inferior  to  either  the  cretaceous  or  the 
argillaceous  earths  for  that  purpose.  The  chief  use  is  in 
correcting  some  of  the  evil  tendencies  and  defects  of 
white  lead  and  zinc  white.  As  correctives,  then,  the 
silicate  earths  are  excellent,  and  are  better  adapted  to 
that  purpose  than  are  the  earth  whites  of  either  of  the 
two  classes  described  before.  Their  benefit  is  great,  and 
the  time  is  not  far  distant  when  a  paint  will  hardly  be 
considered  perfect  that  contains  no  silicate  earth  in  its 
composition. 


WHITE  PIGMENTS  49 

The  above  statement  may  be  considered  by  many 
as  claiming  too  much,  and  it  may  possibly  be  so;  for  it  is 
really  possible  to  make  very  good  paint  without  it,  but 
such  was  not  in  mind  when  it  was  uttered.  The  cost  of 
making  a  good  paint  without  its  use  being  greater,  the 
chances  are  that  there  would  be  but  few  so  made,  and  so 
the  truth  contained  in  the  statement  remains  anyway. 

Composition  and  Chemistry 

Silicate  earths,  as  may  well  be  surmised  and  as  the  name 
indicates,  are  mainly  of  silica  or  sand;  but  this  is  so  fine 
and  the  atoms  so  minute,  that  in  the  best  grades  of  it, 
they  are  held  in  suspension  in  liquids  a  very  long  time  before 
precipitation  takes  place  —  the  particles  will  almost  float. 

The  silicate  earths  occur  in  various  parts  of  the  United 
States  in  natural  beds,  and  for  once  Dame  Nature  has 
endowed  America  with  an  earth  useful  in  painting  which 
is  superior  in  fineness  and  quality  to  anything  that  has 
been  found  so  far  in  any  of  the  European  or  Asiatic 
countries.  The  products  of  American  mines  are  exported 
extensively.  That  will  never  be  the  case  with  its  other 
natural  earth  pigments,  such  as  the  ochers,  umbers,  and 
siennas. 

The  beds  containing  silicate  earths  are  mined  like  all 
the  other  earth  beds,  according  as  to  whether  they  lie 
near  the  surface  or  are  located  quite  a  way  below  it. 
The  raw  earth  is  levigated  to  clean  it  from  heavy  sand  and 
other  impurities,  for  while  it  is  nearly  of  the  same  chemi- 
cal composition  as  sand,  —  which  is  another  form  of 
silica,  —  that  is  as  much  of  an  impurity  in  a  silicate 
earth  as  that  same  sand  would  be  if  found  in  an  ocher. 

In  some  of  the  beds  of  silicate  earths  the  product 
obtained  is  said  to  be  so  nearly  pure  and  free  from  foreign 
matter  as  to  hardly  require  levigation  to  fit  it  for  use. 


50  MODERN  PIGMENTS 

It  is  again  repeated  that  silicate  earths  are  really  not 
pigments  in  the  sense  that  these  can  or  do  impart  color, 
and  their  usefulness  as  correctives  and  for  compounding 
with  other  pigments  is  their  chief  claim. 

Silicate  earths  have  no  affinity  for  water  or  moisture, 
and  are  absolutely  inert  when  mixed  with  linseed  oil,  nor 
will  they  injure  it  in  any  way.  The  atoms  are  so  very 
fine,  that  they  mix  intimately  with  those  of  either  white 
lead  or  zinc  white  to  the  great  benefit  of  both  of  those 
pigments.  They  will  dry  hard  without  any  tendency 
toward  chalking,  cracking,  or  peeling  off,  and,  but  for  its 
lack  of  opacity,  would  be  as  near  the  goal  of  being  an 
ideal  pigment  as  can  be  well  conceived.  Its  use  should 
become  more  popular  than  it  is  now  for  all  kinds  of  out- 
side painting. 

Its  value  can  be  inferred  by  what  can  be  noticed  almost 
anywhere,  or  by  making  the  experiment  for  one's  self 
any  day.  Take  some  white  lead,  or  white  lead  and  zinc, 
either  in  the  pure  white  or  with  color  added  to  make  any 
tint,  and  paint  the  side  of  a  building  with  it  afterwards, 
and  while  the  paint  is  still  fresh,  sand  half  of  it,  then 
notice  what  the  consequences  will  be  —  say  in  five  years. 
The  unsanded  lead  will  be  in  a  bad  state  of  chalking;  the 
lead  and  zinc  will  be  in  a  better  condition,  but  still  will 
begin  to  show  signs  of  decay;  while  that  part  which  has 
been  sanded  will  be  on  as  tight  as  the  day  it  was  put  there. 
The  silica  did  it.  This  is  invariably  the  case;  and  as  it  is 
a  common  practice  for  many  places  exposed  to  being 
marred  or  defaced  to  be  sanded,  one  will  have  little  trouble 
to  find  samples  of  it  already  so  painted  which  have  been 
put  on  for  many  years.  It  can  thus  be  seen  and  the  results 
ascertained  without  having  to  wait  several  years  for  it. 

The  good  wearing  qualities  of  the  French  and  English 
ochers  are  due  to  their  being  silicate  ochers;  they  contain 


WHITE  PIGMENTS  51 

a  large  percentage  of  silica  in  their  base.  (See  the  chapter 
on  ocher.)  Had  the  silicate  earth  but  the  opacity  of 
white  lead,  it  would  be  worth  its  weight  in  gold,  as  the 
saying  is,  as  a  pigment  for  general  painting;  but  it  has 
not  that  quality. 

Many  of  the  most  valuable  colored  pigments  are 
natural  earths  containing  a  large  percentage  of  silica  in 
their  composition,  which  will  be  properly  noticed  under 
the  several  headings  to  which  they  respectively  belong. 

BARYTA  WHITE  (BARIUM  SULPHATE) 
Composition  and  Provenance 

Baryta  white  is  better  and  more  commonly  known  as 
barytes  in  the  United  States.  It  is  found  commercially 
of  many  different  grades  and  qualities.  It  is  obtained  in 
its  natural  state  in  many  parts  of  the  world.  It  is  well 
known  under  the  form  of  "  heavy  spar,"  which  is  a  heavy 
crystalline  rock.  It  is  found  in  localities  of  many-vary- 
ing geological  formations.  Near  Quincy,  Illinois,  it  is  in 
large  quantities  in  the  limestone  formation  of  the  bluffs 
along  the  Mississippi  River,  also  in  the  Blue  Ridge  region 
of  Virginia  and  elsewhere.  Again,  it  is  found  in  the  zinc 
and  lead  mines  of  Southwestern  Missouri,  Northwestern 
Arkansas,  Southwestern  Kansas  and  the  Indian  Territory. 
It  is  somewhat  ludicrous,  this  finding  of  it  in  connection 
with  lead  in  mines  —  as  if  that  substance  knew  that  later 
on  it  should  be  made  to  parade  as  and  become  a  still 
closer  neighbor  of  lead  under  its  new  form  of  "white 
lead/'  and  made  to  renew  an  acquaintance  with  its  old 
neighbor  where  they  had  lain  together  for  ages  before 
being  disturbed  from  their  peaceful  slumber  by  the 
miners. 


52  MODERN  PIGMENTS 

Properties  and  Uses 

Barytes  is  very  transparent.  It  is  the  ideal  trans- 
parent pigment  element,  heavy  spar  being  nearly  as 
transparent  as  glass.  When  ground  in  linseed  oil,  ordi- 
nary barytes  has  no  body.  This  can  be  best  seen  by  the 
mixing  of  barytes  with  oil,  and  of  painting  a  board  three 
coats  with  it,  the  same  mixed  to  the  usual  consistency 
of  paint  for  a  like  purpose.  It  will  be  found  that  these 
three  coatings,  which  had  they  been  mixed  from  any  of 
the  usual  pigments  would  have  covered  the  board  per- 
fectly, in  this  instance  have  not  even  hidden  the  tracery 
of  the  grain  of  the  wood.  It  will  be  safe  to  say  that  one 
single  coat  of  white  lead  would  have  covered  the  surface 
of  the  board  more  opaquely  than  five  coats  of  the  barytes 
paint  would  do. 

That  barytes  must  be  a  very  heavy  substance  may  be 
surmised  from  the  great  weight  of  the  heavy  spar  from 
which  it  is  prepared.  It  is  by  reason  of  this  heavy  weight 
that  it  is  the  chief  adulterant  used  to  doctor  up  white 
lead.  It  being  nearly  of  the  same  specific  gravity,  it  is 
thus  admirably  adapted  to  pass  inspection  where  the 
lighter  weight  of  better  adulterants  would  be  a  "dead 
give  away"  on  account  of  the  greatly  increased  size  of 
a  package  of  a  given  weight.  That  is  why  whiting, 
gypsum,  etc.,  are  so  seldom  used  for  the  purpose  of  adul- 
terating white  lead.  They  would  make  entirely  too  much 
bulk,  and  the  fraud  would  be  recognizable  to  a  novice. 
Therefore  barytes  has  almost  a  monopoly  as  an  adulter- 
ant of  white,  its  heavy  weight  entitling  it  to  that  eminent 
position.  Another  requisite  which  is  of  as  nearly  as 
much  importance,  is  that  of  its  great  transparency.  More 
barytes  can  be  added  to  white  lead  without  muddying 
its  color,  than  of  any  of  the  earth  whites  of  better  body, 


WHITE  PIGMENTS  53 

but  which  change  the  color  of  the  pigments  they  are 
added  to,  as  has  been  already  said  of  them. 

Barytes  is  also  the  adulterant  chiefly  used  in  the  mak- 
ing of  the  cheaper  colors  in  oil;  this,  however,  more  on 
account  of  its  transparency  than  that  of  its  weight;  as  for 
many  of  the  lighter-weight  colors  it  is  greatly  against  it, 
—  it  makes  the  package  look  too  small.  Its  transparency 
usually  decides  the  scales  in  its  favor,  as  the  chief  make- 
weight adulterant  even  for  the  light-weight  colors,  some 
very  light-weight  adulterant  being  used  in  connection 
with  it  to  give  more  bulk.  Its  transparency  does  not 
greatly  affect  the  tone  of  the  darker  colors  with  which 
it  is  used;  and  while  it  can  be  detected  when  the  adul- 
terated color  is  -used  in  making  tints  —  it  renders  them 
less  clear  in  tones  —  it  will  hardly  show  in  the  color  itself 
in  self-color  painting. 

In  such  extra  light-weight  colors  as  Prussian  blue, 
lampblack,  etc.,  it  cannot  possibly  be  used  alone,  as  it 
would  be  an  easy  "give  away;  "  so,  as  was  said,  it  is  usual 
to  marry  it  to  a  much  lighter-weighted  partner,  but  it 
goes  in  just  the  same. 

To  show  the  capacity  of  barytes  as  an  adulterant  and 
its  transparency,  fifty  pounds  of  it  can  be  added  to  one 
pound  of  dry  Prussian  blue  medium  chrome  yellow  or 
lampblack  without  changing  the  colors  greatly.  Thus 
the  enormous  quantity  of  fifty  to  one  is  within  the  possi- 
bilities in  adulterating  with  it.  While  seldom  used  to 
that  extent,  it  is  sometimes  found  in  nearly  that  ratio  in 
the  "cheap  John"  lines  of  colors  in  oil  occasionally  to  be 
seen  —  frequently  more  in  the  cheap  dry  colors. 

While  upon  the  subject  of  adulteration  it  might  be  well 
to  say  here  that  in  a  general  way  colors  are  not  adulter- 
ated to  anywhere  near  the  limit  of  the  possibilities  as 
that  of  fifty  to  one.  More  frequently  the  adulteration 


54  MODERN  PIGMENTS 

will  be  found  to  be  one  to  one,  three  to  one,  or  four  to  one 
of  the  genuine  color;  the  latter  being  the  common  one 
in  use,  and  recognized  as  justifiable  for  the  proprietary 
greens  and  many  other  colors  which  do  not  indicate 
purity  by  any  such  claim  upon  their  labels.  This  adul- 
teration is,  however,  to  such  an  extent,  but  will  be  found 
in  many  whose  labels  would,  to  the  unsophisticated, 
create  the  impression  that  the  colors  were  pure  —  with- 
out saying  that  in  so  many  words. 

As  it  is  mainly  as  an  adulterant  that  barytes  has  any 
serious  claims  upon  the  attention  of  the  readers  of  this 
treatise,  this  is  the  side  from  which  it  is  viewed. 

Not  so,  however,  of  the  artificially  prepared  baryta 
white,  which  is  better  known  to  artists  and  decorators  as 
"blanc  fixe."  The  latter  is  an  excellent  pigment  for 
water-color  painting,  and  nothing  of  what  has  been  said 
of  the  natural  barytes  applies  to  that,  except  its  lack  of 
opacity  in  oil;  but  even  in  that,  it  is  head  and  shoulders 
above  the  ordinary  barytes.  In  water-color  work,  it 
possesses  a  good  body.  It  is  a  perfect  white,  absolutely 
unalterable  under  all  and  any  circumstances  or  conditions. 
It  is  insoluble  in  the  acids,  and  is  not  attacked  by  sulphu- 
reted  hydrogen  gas  nor  any  other  sulphurous  vapors. 
It  is  of  great  value  for  uses  wherever  the  painting  is  sub- 
ject to  such  influences  where  most  of  the  other  whites 
would  be  unsuited.  Its  absolute  permanency  recom- 
mends it  for  the  highest  grade  of  decorative  work, 
and  where  the  reputation  of  a  man  depends  upon 
the  intact  preservation  of  his  work.  It  cannot  be  too 
highly  prized. 

It  has  another  very  important  qualification  aside  from 
those  of  permanency  and  whiteness,  in  that  it  has  a 
peculiar  texture  that  is  entirely  its  own,  and  this  remains 
even  in  the  tints  made  by  its  use.  The  same  pleasing 


WHITE  PIGMENTS  55 

peculiar  finish  cannot  be  reproduced  with  anything 
else,  no  more  than  cotton  can  be  made  to  have  the 
feel  of  wool. 

The  artists  and  decorators  are  the  ones  who  are  mainly 
interested  in  its  use.  It  is  never  likely  to  pass  into  the 
hands  of  the  general  house  painter. 

The  reader  should  remember  to  distinguish  between 
barytes  and  baryta  white  or  blanc  fixe.  Dr.  Dudley,  chief 
chemist  of  the  Pennsylvania  railroad,  has  had  a  great 
deal  to  say  of  it,  and  is  probably  as  good  an  authority 
upon  barytes  in  all  forms  as  can  be  found  the  world  over, 
he  having  made  that  substance  the  subject  of  much 
investigation  and  experiment.  He  says  that  some  forms 
of  the  atoms  in  certain  grades  of  barytes  are  scale-like, 
and  overlap  each  other  in  such  a  way  as  to  intercept  the 
rays  of  light,  and  that  when  colored  up  with  proper  pig- 
ments the  barytes  does  not  show  transparent.  The 
doctor  must  have  come  across  a  brand  that  is  hard  to 
obtain  outside  of  Altoona.  The  author  has  never  yet 
seen  it,  nor  has  he  ever  seen  or  heard  of  any  one  else  who 
has  seen  it  in  such  a  shape. 

There  is  a  legitimate  use  for  barytes  as  an  extender, 
especially  in  such  colors  as  the  greens  or  chrome  yellows, 
which  in  their  pure  state  are  very  strong.  That  state- 
ment should  be  understood  in  this  sense  only:  For 
instance,  one  pound  of  pure  chrome  green  or  chrome 
yellow  is  worth,  say,  25  cents  per  pound.  Another  one 
containing  80  per  cent  of  barytes  can  probably  be  bought 
for  12  cents.  Now  for  solid  painting  the  last  will  go  about 
as  far  as  the  pure,  and  cover  the  surface  well.  The  latter 
will  be  the  cheaper  for  this  use,  so  the  extended  green  or 
yellow  is  the  most  economical  for  solid  painting.  Where 
colors,  however,  are  bought  for  the  making  of  tints,  and 
where  the  amount  of  coloring  matter  they  contain  is  the 


56  MODERN  PIGMENTS 

one  thing  most  needed,  the  pure  color  will  always  be 
found  most  economical. 

The  above  concludes  the  list  of  useful  white  pigments. 

Many  others  have  come  up  from  time  to  time,  staid 
a  little  while  and  were  found  wanting,  or  of  less  value  than 
these  which  have  been  noticed  in  the  two  preceding 
chapters.  They  have  about  all  disappeared,  and  the  list 
of  them  would  read  too  much  like  an  epitaph,  and  would 
be  a  needless  burden. 


CHAPTER  V 
YELLOW  PIGMENTS 

OCHERS 

General  Characteristics 

YELLOW  ochers  are  natural  earths  found  abundantly  in 
all  parts  of  the  known  world.  It  is  of  small  wonder  then 
that  among  the  most  ancient  and  earliest  attempts  at 
chromatic  embellishment  that  have  been  unearthed  and 
brought  to  light  as  a  result  of  searches  made  in  the 
entombed  remains  of  former  civilizations,  many  objects 
are  found  whereupon  ocher  had  been  used  by  some  pre- 
historic decorator. 

This  yellow  was  used  in  the  making  of  many  an  ingen- 
ious design  upon  the  covering  of  the  Egyptian  sarcopha- 
guses.  In  America  the  Aztecs  especially,  and  the  wild 
tribes  of  Indians  roaming  the  plains  and  mountains  of 
North  and  South  America,  used  ocher  also  in  such  decora- 
tions as  they  were  able  to  design  and  execute. 

The  Aztecs  being  the  better  civilized  of  them  all,  one 
would  naturally  expect  more  and  better  decorative  work 
from  them  than  from  the  wild  migratory  tribes;  and 
they  have  not  disappointed  expectation,  as  remains 
of  their  pottery  and  decorated  household  utensils  will 
show. 

In  Asia,  ancient  objects  of  Chinese  and  Tartaric  origin 
have  tracings  of  it  upon  them.  The  Greeks  and  Romans 
used  it  profusely;  and  so  far  there  has  not  been  a  nation 

57 


58  MODERN  PIGMENTS 

found,  where  the  earliest  attempts  at  decorations  have 
been  preserved,  that  ocher  does  not  appear  as  one  of  the 
pigments. 

Of  its  uses  to-day  little  need  be  said.  It  is  a  household 
word,  and  its  praises  are  sung  by  everybody  interested 
in  using  it,  let  him  be  painter,  decorator,  or  artist.  After 
white  lead,  it  is  probably  the  one  color  that  any  of  them 
could  least  afford  to  discard. 

Chemical  Properties  and  General  Character 

All  ochers  are  compounds  or  mixtures  of  several 
ingredients  or  substances.  The  coloring  matter  they  con- 
tain is  due  to  hydrate  ferric  oxide  combined  with  an 
earthy  base  which  varies  with  each  locality,  and  some- 
times with  every  hill  in  the  locality  where  they  are  found. 
They  will  vary  very  much  in  the  same  vein  of  the  same 
bed.  Different  seams  in  the  vein  are  often  of  diverse 
composition,  and  are  sometimes  separated  in  the  mining 
operations. 

There  cannot  be  therefore  any  recognized  standard 
nor  chemical  formula  for  an  article  varying  as  much  as 
this  does.  They  would  have  to  be  changed  with  each 
new  sample  that  was  analyzed. 

Notwithstanding  so  many  variations,  ochers  may  be 
grouped  into  two  general  classes: 

1.  Those  where  the  earth  base  holding  the  iron  oxide 
is  chiefly  of  silicate  earth. 

2.  The  remaining  ochers  whose  base  consists  princi- 
pally of  clay  earths  or  alumina.     There  is  a  vast  difference 
between  these  two  classes  of  ochers,  not  only  in  the  work- 
ing qualities  of  each,  but  in  their  tones  and  permanency. 

Then  there  is  between  the  two  classes  mentioned  above 
an  intermediate  one  comprising  such  as  vary  in  the 
quantity  they  contain  of  either  silica  or  alumina,  making 


YELLOW  PIGMENTS  59 

it  sometimes  difficult  to  class  them  properly,  as  they  come 
to  the  border  line  of  each  of  the  main  groups. 

Mining  and  Production 

Volumes  might  be  written  upon  this  one  pigment 
alone  without  exhausting  the  subject  matter.  While 
it  might  be  attractive  to  a  specialist  in  colors,  much  of 
the  matter  would  have  but  little  interest  to  the  general 
reader. 

Ocher  is  mined  and  obtained  from  the  bowels  of  the 
earth  in  many  different  ways,  depending  upon  the  depth 
required  to  reach  it,  or  to  the  topography  of  the 
surface  of  the  land.  The  price  of  labor  and  advancement 
in  civilization,  and  the  consequent  use  of  labor-saving 
machinery,  come  in  also  as  factors  in  the  problem  of 
mining.  Sometimes  shafts  are  sunk  to  it  in  level 
sections  of  country  if  the  veins  are  deep.  If,  on  the  con- 
trary, they  lie  near  the  surface,  an  open  cut  is  made  to 
the  veins,  and  they  are  simply  elevated,  or,  better  still,  a 
track  is  made  and  the  ocher  shoveled  right  into  the  car. 

In  the  hill  sections  where  it  occurs  as  an  outcrop  above 
the  valleys,  it  is  tunneled  out  and  loaded  in  small  cars 
which  are  run  out  on  a  track  in  much  the  same  manner 
as  coal  under  similar  conditions.  In  many  beds,  seams 
are  found  where  for  a  few  feet  or  inches  a  better  grade 
of  ocher  is  found  than  in  the  rest  of  the  vein.  If  it  be 
found  to  be  very  much  better,  it  is  shoveled  out  separately 
and  handled  by  itself. 

In  its  natural  state,  ocher  is  usually  mixed  with  many 
impurities,  such  as  roots  of  trees  or  plants,  sand,  gravel, 
etc.  For  the  cheaper  grade,  or  what  is  known  as  "  un- 
washed "  ocher,  the  earth  after  having  been  brought 
from  the  mines  is  simply  sifted  through  a  screen  and 
barreled.  Only  the  very  lowest  or  ordinary  ocher  is  sold 


60  MODERN  PIGMENTS 

in  that  way,  and  the  bulk  of  it  is  washed,  and  the  very 
fine  qualities  re  washed ;  but  with  the  system  of  continuous 
settling  tanks  it  is  seldom  practiced  any  more,  as  the 
very  finest  can  be  obtained  from  the  farthest  tanks. 
This  is  equal  practically  to  rewashing,  and  the  method 
was  described  under  the  heading  of  "Whiting."  It  is 
needless  to  repeat  it  in  this  connection,  as  it  is  the  same, 
there  being  no  difference  in  the  operation  nor  its  principles. 

As  already  told,  the  finest  is  that  which  settles  in  the 
tanks  situated  the  farthest  from  the  outpour,  and  the 
settlings  are  graded  accordingly  as  extra  fine,  superfine, 
double  washed,  single  washed,  etc.  These  washings  or 
levigations  are  no  index  to  the  quality  of  an  ocher,  and 
only  signify  the  greater  or  lesser  freedom  from  impurities 
contained  in  the  ocher. 

There  is  still  another  method  of  mining  ocher,  which  is 
sometimes  employed  in  hilly  countries.  A  dam  is  built 
across  a  valley  with  a  sluiceway  at  its  lowest  level,  through 
which  the  water  from  the  pound  resulting  from  damming 
the  valley  can  be  let  out  or  kept  in  by  shutting  the  gate  in 
the  sluiceway. 

After  the  heavy  spring  and  early  summer  rains  are  over, 
the  mining  commences.  Hydraulic  machinery  is  used, 
and  streams  play  upon  the  ocher  beds  in  the  hills  adjacent 
to  the  valley.  This  dissolves  them  and  washes  down  the 
earth  into  the  pent-up  valley  below;  after  a  sufficient 
quantity  has  been  washed  out,  which  is  gauged  by  the 
capacity  of  the  pond  formed  by  the  dam,  it  is  allowed 
to  settle.  When  the  water  has  cleared,  it  is  allowed  to 
escape  through  the  sluiceway,  while  the  ocher  remains 
as  a  pulpy  deposit.  It  is  left  in  that  state  to  dry  out  by 
the  action  of  the  sun's  rays.  This  requires  some  little 
time,  and  in  wet  seasons  there  is  considerable  risk  attached 
to  this  method  of  mining;  but  there  is  usually  nice  weather 


YELLOW  PIGMENTS  61 

in  the  autumn,  when  it  is  taken  advantage  of  to  handle  the 
ocher. 

By  this  system  the  heavier  impurities  are  deposited 
long  before  reaching  the  pond,  and  little  else  than  the 
ochered  water  reaches  there,  as  the  gravel  and  roots  are 
screened  out  early  in  the  runways  through  which  the 
flow  is  made  to  reach  the  pond.  The  sand  settles  all 
along  its  course,  or  at  its  first  entering  into  the  pond;  that 
which  has  been  held  in  solution  until  it  reaches  the  main 
part  of  the  depositing  pond  being  usually  a  fair  quality  of 
ocher  which  requires  no  further  washing  for  ordinary  use. 

When  the  pulp  has  dried  sufficiently,  teams  are  set  to 
work  with  plows  and  scrapers,  and  are  loaded  with  the 
loosened  ocher  earth  and  hauled  out  to  the  packing  sheds, 
which  are  roughly  constructed  affairs,  but  sufficiently  tight 
to  keep  the  ocher  from  rain  and  consequent  damage. 
There  it  is  again  pulverized,  screened,  barreled,  and  placed 
either  in  cars  for  shipment  or  in  storage  warehouses. 

This  method  is  by  far  the  cheapest  way  of  handling 
ocher,  but  it  is  limited  in  that  it  cannot  be  made  contin- 
uous. It  is  ingenious,  and  might  have  been  the  invention 
of  a  Down  East  Yankee,  but  that  is  not  so.  It  is  that  of  a 
plodding  Pennsylvania  Dutchman;  at  least,  he  was  the  first 
one  to  put  the  system  into  use  in  America,  and  possibly 
in  the  whole  world.  His  works  are  situated  near  Allen- 
town,  Pennsylvania,  and  are  located  in  a  small  valley 
through  which  is  a  runlet  which  gives  the  water  a  chance 
to  reach  the  larger  streams,  but  which  is  usually  dry 
except  during  the  heavy  spring  rains. 

Properties  and  Uses 

The  statement  was  made  that  ochers  could  be  grouped 
into  two  general  classes,  and  so  they  may  for  the  purpose 
of  examining  their  characteristics  and  properties. 


62  MODERN  PIGMENTS 

The  two  extremes  are  taken  as  types,  but  in  reality 
there  are  some  ochers  that  are  so  near  the  half-way  mark 
between  the  two  types,  that  it  takes  a  good  deal  of  guess- 
ing to  tell  where  they  rightly  belong.  Besides,  there  are 
any  number  of  grades  from  the  one  type  down  toward  the 
dividing  line  forming  the  line  of  demarcation  of  the  other. 
Speaking  in  a  general  manner,  the  bulk  of  European  ochers 
belongs  to  the  class  of  ochers  containing  a  silicate  base, 
while  those  found  so  far  in  America  are  more  argillaceous 
or  alminous  in  character,  and  may  be  so  classed. 

If  the  reader  bears  in  mind  what  was  said  concerning 
the  silicate  white  earths  under  that  heading,  he  will  have 
no  trouble  to  understand  why  ochers  with  a  silicate  base 
are  much  better  than  those  having  a  clay  base,  at  least  for 
the  painting  of  surfaces  exposed  to  the  weather.  He  will 
also  understand  why  the  clay  ochers  are  best  adapted  to 
distemper  work. 

One  half  of  the  lamentations  which  many  painters 
indulge  in  because  of  the  troubles  they  have  had,  caused 
by  the  use  of  ocher,  and  in  the  airing  of  which  they  at 
times  fill  the  columns  of  the  trade  papers,  can  be  easily 
traced  to  the  use  of  the  wrong  ocher.  Investigations 
will  always  show  that  it  was  an  ocher  with  a  clay  base 
that  was  the  disturbing  element. 

One  never  hears  of  troubles  from  those  painters  who 
use  the  silicate-based  ochers  under  the  very  same  condi- 
tions where  the  other  kind  is  said  to  have  gone  wrong,  and 
these  can  hardly  find  words  good  enough  to  utter  the 
approval  they  have  to  give. 

Both  are  truthful  in  the  telling  of  their  experiences,  but 
while  each  has  to  tell  them  from  the  use  of  a  pigment 
which  has  the  same  name  and  possibly  the  same  color, 
each  is  in  reality  speaking  of  something  of  an  entirely 
different  nature  and  properties. 


YELLOW  PIGMENTS  63 

The  troubles  had  by  those  who  used  the  clay  ochers 
are  of  the  same  nature  as  those  to  be  expected  from  the 
use  of  china  clay,  as  has  been  related  in  the  former  chapter. 
Clay  ochers  when  thoroughly  dry  have  parted  with  the 
moisture  which  they  originally  contained.  If  a  building 
is  primed  with  such  an  ocher,  it  may  be  called  hermeti- 
cally sealed,  especially  if  the  priming  was  a  heavy  one,  as  is 
usually  put  on  for  cheap  two-coat  work.  This  heavy 
priming  has  practically  sealed  up  the  wood  and  prevented 
the  penetrating  of  the  second  or  finishing  coat,  the  fine 
particles  of  the  clay  and  oil  combining  to  make  a  poreless 
glazed  surface.  The  supervening  coat  put  over  it  dries 
in  much  the  same  way  as  it  would  upon  a  piece  of  glass; 
it  is  not  able  to  anchor  itself  into  the  non-porous  priming. 
If  the  priming  had  been  composed  of  white  lead  alone,  or 
of  white  lead  with  a  reasonable  quantity  of  zinc  with  it, 
and  put  on  not  too  heavy,  the  priming  would  have  been 
porous.  The  finishing  coat  of  lead,  or  lead  and  zinc,  put 
over  a  heavy  clay  ocher  priming,  dries  upon  the  surface 
without  clinching  itself  to  it,  because  it  is  non-porous. 
This  coat  naturally  dries  thoroughly,  having  contact 
with  the  atmosphere,  and  becomes  porous  after  the  linseed 
oil  has  lost  its  glyceride.  The  ocher  underneath  is  reached 
through  these  pores  by  the  moisture  in  wet  weather, 
which  it  will  absorb  in  sufficient  quantity  to  make 
trouble.  During  dry,  hot  weather,  this  absorbed  moisture 
will  be  drawn  out  of  it  in  the  form  of  steam  or  vapor. 
Much  of  it  will  escape  through  the  same  pores  by  which 
it  entered,  but  some  may  not  because  of  a  surplus  of 
moisture  finding  its  way  to  some  porous  part  of  the  wood, 
and  when  the  heat  is  great,  the  steam  not  being  able  to 
escape  as  fast  as  it  is  formed,  forms  a  blister  under  the 
coat  or  coats  applied  over  the  clay  ocher  priming,  and  there 
is  trouble.  This  absorption  and  evaporation  continually 


64  MODERN  PIGMENTS 

going  on  tend  in  time  to  loosen  the  superadded  coat  or 
coats  and  to  make  them  part  company  from  the  priming, 
which  usually  remains  intact.  This  is  one  of  the  main 
causes  of  complaint  made  against  the  use  of  ocher  as  a 
primer. 

Silicate  ochers  have  no  such  effect.  Silica  does  not 
absorb  water.  It  has  no  affinity  for  it,  consequently 
there  can  never  be  any  of  it,  either  by  absorption  or  other- 
wise, to  escape  out  of  it  in  the  form  of  steam  during 
warm  weather,  so  that  there  is  no  danger  of  the  super- 
added  coats  coming  off  it,  as  related  of  the  clay  ocher. 
Being  more  porous,  the  finishing  coat  becomes  anchored 
to  it,  and  if  it  has  been  properly  compounded  will  remain 
attached  as  long  as  it  would  upon  a  lead  priming.  It  is, 
of  course,  possible  to  mix  a  finishing  coat  of  dope,  but 
such  would  come  off  of  anything  it  was  applied  upon,  and 
this  is  not  a  matter  for  serious  consideration. 

All  kinds  of  ochers  are  great  absorbents  of  linseed  oil, 
and  should  be  bought  ground  in  oil  rather  than  in  the 
dry  state,  unless  one  possesses  good  grinding  machinery, 
which  is  something  very  unusual. 

As  may  be  readily  understood,  the  mere  percentage  of 
strength  of  the  colored  matter  (hydrate  ferric  oxide)  con- 
tained in  an  ocher  is  not  always  a  criterion  whereby  to 
judge  of  its  quality  or  actual  value.  The  better  grades  of 
French  ochers  seldom  contain  as  much  as  25  per  cent  of 
ferric  oxide,  and  usually  much  less  than  that. 

Every  painter  and  decorator  is  pretty  well  acquainted 
with  the  high  character  of  some  of  the  French  ochers, 
also  with  some  of  the  English  of  the  Oxford  class.  These 
last  are  considered  the  best  found  in  England,  and  justly  so. 

The  following  analysis  is  taken  from  Church's  "Chemistry 
of  Paints,"  and  was  made  by  Professor  Church  himself 
from  a  sample  of  ocher  which  was  taken  from  the  Shotover 


YELLOW  PIGMENTS  65 

Hill  mines  near  Oxford,  and  which  he  says  represents 
fairly  the  quality  of  the  Oxford  ochers: 

Hygroscopic  moisture 7.1 

Combined  water 9.0 

Ferricoxide    .    .....    ......;.    .  13.2 

Alumina 6.3 

Silica .    .    .  -.    .    .  61.5 

Calcium  sulphate .'  ..    .    .  1.4 

Undetermined 1.5 

100 

The  above  analysis  shows  nearly  two  thirds  of  the  com- 
ponent parts  of  that  ocher  to  consist  of  silica,  therefore 
one  can  pin  his  faith  to  it  for  all  kinds  of  outdoor  painting. 
But  note  the  comparatively  small  percentage  of  ferric 
oxide,  the  coloring  matter. 

The  French  ochers  proper  are  somewhat  richer  in  the 
proportion  of  oxide  of  iron  contained  in  them  than  that 
of  the  sample  cited  above.  Notwithstanding  that  they 
average  stronger  in  coloring  matter  than  the  Oxford 
ochers,  they  are  commonly  of  a  lighter  and  brighter  tone. 
This  is  remarkable,  because  ochers  which  usually  contain 
large  proportions  of  ferric  oxide,  are  darker  than  those 
which  contain  less.  It  is  very  hard  to  account  satis- 
factorily why  it  is  that  some  samples  are  so  much  richer 
in  tone  than  others  of  nearly  the  same  chemical  compo- 
sition. Some  lack  in  brilliancy,  or,  if  not  in  that,  are  found 
lame  elsewhere.  It  is  therefore  useless  to  look  to  a 
chemical  analysis  for  a  reason  to  explain  these  things. 

Some  of  the  better  grades  of  French  ochers  make 
beautiful  cream  and  buff  tints  with  white  lead  or  zinc 
white  —  so  rich  in  fact  as  to  suggest  to  one  used  only  to 
the  American  ochers  that  possibly  they  had  been  doc- 
tored up  with  chrome  yellow.  This  richness  is  inherent, 


66  MODERN  PIGMENTS 

and  the  tints  made  from  them  will  never  fade,  as  would 
those  from  a  chromed  ocher. 

It  is  customary  with  many  color  grinders  to  tone  up 
ochers  with  chrome  yellow.  When  this  is  done,  and  sold 
under  the  proper  name,  and  labeled  as  a  "Chrome  Ocher," 
it  is  all  right.  That  is  a  legitimate  transaction;  but 
when  this  is  done  to  tone  up  a  poor  ocher  so  that  it  will 
sell  better,  then  it  is  all  wrong,  and  is  bound  to  work  an 
injury  upon  the  unwary  users  of  it. 

If  such  ochers  are  used  for  solid  painting,  the  chrome 
yellow  will  fade  away,  leaving  the  ocher  its  original  ugly 
color.  If  such  an  ocher  has  been  used  in  making  tints, 
the  rich  tone  will  disappear  even  more  quickly. 

The  painter  using  these  may  possibly  have  saved  a 
quarter  of  a  dollar  in  the  difference  of  cost  between  a 
good  French  ocher  and  what  he  used  in  the  making  up 
of  his  tint  if  the  house  was  a  good-sized  one,  but  in  repu- 
tation the  loss  cannot  be  computed  in  quarter  dollars. 
Had  he  used  the  right  ocher,  the  gain  would  have  been 
permanent;  the  customer  would  have  been  better  satis- 
fied, even  if  he  knew  little  about  color.  Every  neighbor 
seeing  the  house  holding  its  color  so  well  and  so  long 
would  have  become  a  free  "ad"  for  the  painter.  The 
wishy-washy,  fady,  spotty-looking  house  is  another 
kind  of  an  "ad"  loudly  proclaiming  that  the  man  who 
did  the  job  did  not  know  his  business. 

Page  after  page  of  ocher  analyses  might  be  given,  but 
would  only  confuse  the  mind.  All  they  do  or  would 
prove  is  that  there  is  no  such  thing  as  uniformity  to  be 
found  in  them,  and  this  has  been  said  so  often  here  that 
it  is  unnecessary  to  prove  it  again  by  crowding  in  useless 
testimony. 

The  reader  has  been  advised  to  buy  his  ocher  ground 
in  oil.  There  are  good  reasons  for  it.%  Manufacturers 


YELLOW  PIGMENTS  67 

of  reputation  are  much  more  careful  buyers  than  the 
average  painter  can  be.  They  know  how  and  where  to 
buy  pure  French  ochers.  They  have  men  in  their  employ 
who  are  experts  in  this  line.  They  can  buy  direct  from 
the  importers,  if  it  be  so  that  they  do  not  import  it  them- 
selves, and  will  receive  it  in  the  original  packages  from 
the  custom  house  as  imported.  The  painter  who  thinks 
he  can  tell  unerringly  a  French  ocher  when  he  sees  it,  or 
who  depends  upon  the  stenciled  marks  on  the  barrels 
bought  from  his  supply  houses  or  the  jobbers,  will  in  nine 
cases  out  of  ten  be  imposed  upon.  Besides,  the  best 
reason  of  all  is,  that  allowing  he  can  buy  just  the  same  as 
the  manufacturer,  he  certainly  cannot  afford  to  grind  it. 
The  grinding  of  a  good  ocher  should  never  be  done  in 
an  iron  mill,  as,  when  it  is  so  ground,  it  is  likely  to  lose 
brilliancy,  or  at  least  impair  some  richness.  Stone  mills 
are  the  only  ones  fit  for  grinding  ocher,  or,  for  that  matter, 
all  other  colors,  including  the  blacks,  if  brightness  of  the 
color  is  of  any  object  —  and  it  surely  ought  to  be.  The 
above  is  said  for  the  benefit  of  the  painter  who  is  thinking 
about  the  buying  of  a  paint  mill  so  he  can  buy  his  colors 
dry  and  pure  (?),  and  save  his  hard-earned  dollars  instead 
of  giving  them  away  for  colors  ready  ground.  The  man 
who  owns  a  collection  of  paint  mills,  and  has  them 
rusting  away  down  in  the  back  part  of  the  cellar,  knows 
better,  and  the  advice  given  does  not  concern  him.  All 
the  money  that  a  painter  has  ever  saved  by  the  grinding 
of  his  own  colors  can  be  put  inside  of  a  very  small  pocket 
book,  and  in  old-fashioned  copper  cent  cart-wheels  at 
that. 

Grinding  colors  so  that  they  retain  their  brilliancy  of 
tone,  and  are  ground  to  the  last  degree  of  fineness,  is  a 
science  and  trade  by  itself.  The  painter  can  never  learn 
it  thoroughly,  nor  can  he  equip  himself  rightly  for  it  except 


68  MODERN  PIGMENTS 

at  too  great  an  expense  for  it  ever  to  pay  him  to  do  so. 
There  is  quite  a  capital  tied  up  in  such  an  equipment, 
which  in  an  ordinary  shop  will  be  required  to  work  for 
possibly  one  week  out  of  the  fifty-two  in  the  year.  This 
machinery  will  have  to  lie  idle  fifty-one  weeks  yearly. 
There  will  be  nothing  for  it  to  do.  If  he  intends  to  keep 
it  going  so  as  to  sell  to  others,  all  right  and  good  —  but 
then  the  painter  will  find  it  more  profitable  to  give  up 
the  painting  business,  as  he  cannot  expect  to  make  a 
success  of  both  at  the  same  time. 

There  are  few  shops,  aside  from  those  of  large  railway 
systems,  where  the  grinding  of  colors  has  ever  been  done 
advantageously.  In  these  there  is  a  set  of  men  whose 
sole  business  it  is  to  attend  to  the  grinding,  and  who,  if 
they  are  not  expert  grinders  at  the  beginning,  soon  become 
skilled  by  keeping  constantly  at  it.  Even  in  these  large 
shops  there  is  no  economy  claimed  by  the  master  mechan- 
ics. The  cost  of  installing  and  maintaining  the  grind- 
ing plant,  and  the  wages  of  the  employees  detailed  to 
that  work,  more  than  eat  up  the  difference  in  cost  between 
the  dry  pigments  and  the  ground  goods  prepared  ready 
for  thinners,  bought  in  large  quantities,  as  these  shops  do. 

The  large  capital  invested  in  expensive  machinery 
which  is  constantly  needing  repairs  soon  disgusts  the 
most  enthusiastic,  and,  like  all  dearly  bought  experience,  it 
comes  to  stay  with  them.  Hence  the  discarded  machinery 
in  the  cellar,  or  that  which  goes  to  the  scrap-iron  heap. 

This  lengthy  advice  and  warning  is  given  here,  not  so 
much  because  it  appertains  to  ocher  more  than  to  any 
of  the  other  colors,  but  because  ochers  being  the  first  ones 
of  the  colored  pigments  under  consideration,  it  seemed 
best  to  give  it  under  that  head,  and  it  will  not  have  to  be 
repeated  again.  Such  advice  and  warning  is  needed, 
and  if  followed  it  will  save  dollars  to  the  man  heeding  it. 


YELLOW  PIGMENTS  69 

During  a  lifetime,  the  author  has  visited  in  one  capacity 
or  another  for  nearly  fifty  years  several  thousand  paint 
shops.  In  a  very  few  he  has  seen  mills  set  up;  in  many 
more  he  has  seen  the  self-same  mills  relegated  to  some  out- 
of-the-way  place.  In  all  instances  where  the  owners  were 
asked  about  the  saving  effected  by  their  use,  the  reply  has 
been  —  nothing. 

Upon  returning  after  a  year's  absence  to  shops  where 
they  had  been  set  up,  they  had  disappeared,  and  the  same 
answer  was  received  as  the  reason  for  their  removal. 

As  nearly  all  the  characteristics  presented  so  far  apper- 
tain mainly  to  the  class  of  ocher  known  as  the  "  silicate  " 
or  the  French  and  English,  more  will  be  said  now  of  the 
special  characteristics  which  belong  to  the  other  or 
argillaceous  class  —  those  where  the  clay  base  predom- 
inates. 

Reasons  have  been  given  why  the  silicate  ochers  were 
the  best  for  outside  painting,  and  why  they  should  be 
used  for  that  purpose  to  the  exclusion  of  the  clay  ochers. 
But  for  distemper  or  water-color  work  the  French  and 
English  ochers  are  not  nearly  as  well  adapted  as  the 
American  clay  ochers. 

Most  people  are  better  acquainted  with  them  under  the 
name  of  American  ocher  than  any  other.  In  the  markets, 
the  division  of  ochers  into  the  silicate  or  clay  classes  is 
unknown.  The  French  and  English  or  the  American 
in  various  grades  is  all  the  classification  they  receive. 
To  all  intents  and  purposes  it  really  amounts  to  the  same, 
as  the  imported  represents  the  silicate  class,  and  the 
American  the  clay  class,  because  about  all  found  so  far 
in  America  partake  more  or  less  of  this  character. 

In  distemper  painting,  clay  ochers  work  better.  They 
cover  better,  and,  what  is  still  more  prized,  they  look  better 
than  the  silicate  class  does;  so  that  what  they  lack  for  oil 


70  MODERN  PIGMENTS 

painting  becomes  their  chief  redeeming  quality  in  water- 
color  work. 

This  class  of  ocher  is  very  common.  It  is  found  in 
nearly  all  if  not  in  every  state  in  the  Union.  Like  the 
other  ochers,  it  varies  very  much  in  composition.  So  far, 
the  best  that  have  been  found  are  mined  in  Eastern  Vir- 
ginia on  the  Appomattox  River  below  Petersburg,  and 
in  the  same  section  at  Bermuda  Hundreds. 

Those  Eastern  Virginia  ochers  contain  a  fair  per- 
centage of  silica  in  their  base,  but  the  alumina  predomi- 
nates. They  carry  about  25  per  cent  of  ferric  oxide. 
Their  tone  is  fair,  and  they  may  be  said  to  be  the  nearest 
approach  to  the  imported  —  many  jobbers  sell  them  as 
"  Rochelle."  These  represent  the  better  grade  of  American 
ochers  found  so  far. 

On  the  other  extreme  —  in  Missouri  down  on  the 
Iron  Mountain  railroad  below  St.  Louis  —  there  are  found 
numerous  beds  of  ocher.  The  remarkable  peculiarity  of 
these  ochers  is  the  enormous  quantity  of  ferric  oxide 
they  carry.  Some  samples  analyze  as  much  as  85  per  cent 
ranging  down  to  20  per  cent.  A  fair  average  for  that 
section  will  be  more  than  double  that  of  the  imported 
class.  But  what  the  oxide  of  iron  makes  up  in  quantity 
it  seems  to  lose  in  quality,  the  tone  being  universally 
poor. 

Their  chief  use  so  far  has  been  found  in  the  burning 
of  them  into  a  red  ocher  and  in  compounding  them  with 
talc  in  the  making  of  a  cheap  Venetian  red  or  rather 
mortar  color  for  which  they  are  excellent,  being  so  strong. 
Enormous  quantities  are  sold  for  that  purpose  alone. 

Some  of  these  very  strong  American  ochers  are  also 
compounded  with  ground  talc,  gypsum  or  silicate  earths; 
some  being  sold  as  French  and  English,  but  the  bulk 
going  under  the  American  name. 


YELLOW  PIGMENTS  71 

Most  of  the  American  ochers  are  semi-transparent,  and 
but  for  their  tones  could  be  classed  with  perfect  propriety 
with  the  siennas.  Some  which  do  come  nearest  to  them 
are  so  classed  and  sold  as  American  siennas.  This  trans- 
parency is  not  apparent  in  distemper  painting,  but  it 
becomes  decidedly  objectionable  for  oil  painting,  even 
when  compounded  with  silicate  earths,  and  thus  rendered 
unobjectionable  in  all  other  respects. 

In  addition  to  the  natural  ochers,  tons  upon  tons  of  that 
pigment  are  made  artificially.  When  a  good  quality 
of  ferric  oxide  is  used  as  the  coloring  agent,  and  a  right 
base  selected  to  hold  it  up  just  right,  the  product  can 
hardly  help  being  a  good  one.  There  surely  cannot  be 
any  good  reasons  given  why  an  excellent  artificial  ocher 
should  not  be  made  as  well  as  an  artificial  Venetian  red, 
which  these  all  are.  What  is  said  under  the  heading  of 
that  pigment  regarding  preparation  will  give  the  reader 
an  idea  of  how  these  artificial  earths  are  produced  and 
prepared  for  use.  There  is  this  difference,  however,  that 
in  the  case  of  ochers  no  calcination  is  necessary  —  all  that 
is  needed  is  mixing  and  triturating.  The  base  is  usually 
either  china,  clay,  talc  and  silicate  earth  in  such  propor- 
tions as  best  suit  the  compounders. 

The  great  trouble  heretofore  has  been  in  the  finding  of 
an  hydrate-ferric  oxide  of  sufficient  richness  to  compete 
with  the  French  and  English  imported  ochers.  So  far, 
all  these  artificial  ochers  have  had  a  lame  side  in  that  they 
are  all  too  transparent  in  oil  to  be  palmed  off  as  genuine 
French  ocher  upon  the  expert  ones  at  least. 

For  all  that,  the  French  and  English  ochers  are  silicious; 
they  are  very  opaque,  much  more  so  than  any  sample  of 
American  containing  twice  the  quantity  of  coloring  matter. 
It  looks  as  if  the  atomic  formation  of  the  hydrate-ferric 
oxide  from  over  the  water  was  somehow  different  from 


72  MODERN  PIGMENTS 

that  produced  on  this  side  of  the  big  pond  —  or  is  this  due 
to  the  forms  of  atoms  in  some  of  the  bases?  There  seems 
to  be  an  opening  here  for  scientists  to  investigate. 

This  kind  of  transparent  ferric  oxide  appears  to  be 
found  in  Italy,  as  many  of  the  Italian  siennas  contain 
twice  as  much  as  many  of  the  French  ochers,  and  yet  they 
are  very  transparent  for  all  that. 

As  soon  as  the  proper  hydrate-ferric  oxide  can  be 
found  or  artificially  produced  with  as  good  tone  as  that 
in  the  imported  ochers  and  as  opaque,  so  that  they  can 
be  duplicated  at  will  here,  there  will  be  as  little  French 
and  English  ochers  imported  as  there  is  now  of  English 
Venetian  red.  In  all  likelihood  it  is  only  a  question  of 
time  when  this  will  take  place.  All  signs  point  that 
way  now,  and  the  painter  will  gladly  hail  the  day  when 
he  can  depend  to  a  nicety  upon  the  uniformity  and  exact 
composition  of  his  ochers. 

Some  of  these  artificial  ochers  that  have  been  very 
carefully  compounded,  can  be  relied  upon  as  being  very 
superior  for  outside  painting  to  those  that  are  mined 
and  that  are  of  uncertain  composition.  Samples  which 
were  examined  and  tested  show  up  nearly  as  good  as 
many  that  are  imported. 

As  ocher  is  the  most  important  of  all  the  colored  earth 
pigments  to  the  painter,  no  apology  is  needed  for  having 
given  so  much  space  to  its  consideration. 


CHAPTER  VI 

CHROME  YELLOW 

YELLOW   PIGMENTS     (Continued) 

General  Remarks  Concerning  Them. 

THE  chrome  yellows  follow  the  ochers  in  the  list  of 
yellow  pigments,  and  rank  next  to  them  in  usefulness  and 
importance  to  the  painter. 

These  yellows  are  all  chemically  made  in  color  works, 
and  are  found  of  various  tones  covering  the  whole  range, 
from  a  deep  orange  bordering  upon  a  true  red  to  the 
lightest  of  the  canary  yellows. 

Commercially  they  are  known  as  "canary  yellow," 
which  is  the  palest;  "lemon  yellow"  comes  next  to 
that  in  paleness ;  "  medium  chrome  yellow  "  is  the  neu- 
tral chromate  of  lead,  and  its  shade  borders  neither 
towards  the  orange  nor  the  lemon.  It  is  neutral  in  this 
respect  as  well  as  chemically.  "Orange  chrome  yellow" 
runs  in  a  variety  of  shades  from  a  very  pale  tinge  of 
that  color  to  a  deep  —  almost  scarlet  —  shade  of  it. 
Some  manufacturers  make  it  up  in  three  shades, 
which  they  mark  as  "pale  orange,"  'orange,"  and 
"deep  orange." 

The  medium  chrome  yellow  is  the  only  one  of  the  whole 
range  that  is  the  true  "chromate  of  lead."  The  varia- 
tions from  it  are  due  to  the  addition  of  other  substances 
added  purposely  to  produce  them.  So  the  medium  or 
neutral  chromate  of  lead,  is  the  base,  or  standard,  from 

73 


74  MODERN  PIGMENTS 

which  all  the  others  are  mere  variations.     For  this  reason 
its  character  will  be  the  first  one  considered. 

MEDIUM  CHROME  YELLOW 
Its  Characteristics,  Chemistry,  and  Manufacture 

Chrome  yellow  has  been  known  under  various  names 
for  over  a  century.  As  its  name  indicates,  it  is  derived 
from  chromic  acid  and  a  lead  base. 

It  is  easily  obtained  as  a  precipitate  by  simply  making 
solutions  of  the  acetate  or  of  the  nitrate  of  lead,  which 
are  soluble  in  water,  and  of  bichromate  of  potash,  and 
pouring  the  two  solutions  together  in  a  settling  tank. 
The  chrome  yellow  will  instantly  precipitate. 

Color  manufacturers,  however,  make  it  from  white  lead, 
as  it  is  more  economical  to  produce  in  that  way.  This 
being  insoluble  in  water,  requires  more  manipulations 
and  boiling.  The  proportions  used  are  about  four  pounds 
of  white  lead  to  one  of  the  bichromate  of  potash. 

CANARY  AND  LEMON  CHROME  YELLOW 
Manufacture 

The  lighter  shades  of  chrome  yellow  are  made  in 
precisely  the  same  manner  as  the  ,neutral  chromate 
of  lead  or  medium  chrome  yellow,  with  this  difference: 
lead  sulphate  or  sulphuric  acid  must  be  added  to 
the  white  lead  and  bichromate  of  potash.  According, 
therefore,  to  the  quantity  of  the  sulphate  of  lead  added, 
will  be  the  canary,  lemon,  or  intermediate  light  shades. 
The  more  sulphate  of  lead  that  goes  in  the  mixing  liquids, 
the  lighter  will  be  the  shade;  the  less  of  it  used,  the  nearer 
will  it  approach  to  that  of  the  medium  chrome  yellow. 

Sulphate  of  lead  is  a  legitimate  component  part  of  a 
pale  chrome  yellow,  however  much  of  an  adulterant  it 


YELLOW  PIGMENTS  75 

may  be  when  added  to  an  already  made  and  precipitated 
medium  chrome  yellow  or  an  orange  shade  where  it  has 
no  business  to  be,  and  where,  if  found,  it  is  a  sure  indication 
of  adulteration. 

The  sulphate  of  lead  must  be  added  before  the  precipi- 
tation of  the  solutions  so  as  to  produce  the  lighter  shades, 
as  it  combines  with  them  then,  which  it  will  not  do  if 
added  afterward. 

Sulphate  of  lead  is  frequently  used  as  an  adulterant 
of  medium  chrome  yellow  by  simply  mixing  the  two  by 
trituration.  In  such  a  mixture  the  color  of  the  medium 
yellow  is  not  changed. 

Chemists  who  are  not  familiar  with  this  fact,  and  who 
have  not  made  the  study  of  paint-making  a  specialty, 
frequently  make  queer  mistakes  in  their  analysis.  They 
know  that  chrome  yellow  is  neutral  chromate  of  lead,  so 
that  when  the  lighter  samples  of  chrome  yellow  are  handed 
to  them  for  analysis  they  are  sure  to  call  the  sulphate  of 
lead  they  are  bound  to  find  in  it  an  adulterant,  not  know- 
ing enough  about  color-making  to  make  the  proper  allow- 
ance for  the  difference  in  the  shade  between  that  and  the 
medium.  It  is  only  when  found  in  a  medium  chrome 
yellow,  where  it  has  no  business  to  be,  that  it  can  be 
considered  an  adulterant. 

As  these  light  shades  of  chrome  yellow  vary,  so  much,  it 
is  impossible  to  give  the  exact  amount  of  sulphate  of  lead 
they  should  contain. 

Alum  and  barytes  are.  sometimes  used  to  lighten  the 
tones,  but  principally  as  adulterants. 

ORANGE  CHROME  YELLOW 
Manufacture 

Orange  chrome  yellows  are  the  opposite  of  the  lemons. 
It  has  been  shown  that  in  the  lemon  and  canary  chrome 


76  MODERN  PIGMENTS 

yellows,  the  change  of  tone  from  that  of  the  medium  was 
due  to  the  addition  of  an  excess  of  acid  in  the  form  of 
sulphate  of  lead  or  sulphuric  acid. 

In  the  orange  chrome  yellows,  the  deepening  of  tone 
and  reddish  hue  is  due  to  an  excess  of  alkali  from  the  use 
of  some  caustic  substance.  It  may  be  obtained  in  many 
different  ways,  but,  after  all,  the  difference  is  in  the  caustic 
substance  added  to  the  white  lead  and  bichromate  of 
potash.  As  stated  under  the  lemon  yellows,  they  must 
be  added  to  the  chromate  of  lead,  or  rather  to  the 
solutions  of  chemicals  which  are  equivalent  thereto, 
and  the  whole  precipitated  together.  The  alkaline 
substances  mainly  employed  for  this  purpose  are 
caustic  soda  or  caustic  potash.  The  greater  the  quantity 
of  these  used,  the  redder  will  be  the  tone  of  the  orange 
chrome  yellow. 

In  an  analysis  of  orange  chrome  yellow  there  will  be 
found,  besides  chromate  of  lead,  either  lime,  soda,  or 
potash,  according  to  which  of  those  substances  was  used 
before  the  striking  of  the  precipitate.  Therefore,  accord- 
ing to  the  quantities  of  the  alkali,  the  various  hues  and 
shades  of  orange  are  produced  from  the  faintest  tinge  of 
orange  to  those  of  near  approach  to  a  fiery  red.  There 
can  be  no  formula  given  of  the  proper  amount  to  use  for 
the  producing  of  any  given  shade.  The  manufacturers 
hardly  ever  strike  duplicates  of  any  shade,  but  produce 
hundreds  which  are  not  alike.  They  do  grade  and  mix 
many  together  which  will  give  a  fair  average  for  the 
standard  they  have  adopted  for  the  required  shades  of  it. 

Properties  and  Uses  of  Chrome  Yellow 

Chrome  yellows  of  all  shades  and  hues  have  about  the 
same  general  characteristics  and  properties,  qualities  and 
defects.  It  is  proper,  therefore,  to  bunch  them  together, 


YELLOW  PIGMENTS  77 

and  to  review  them  under  the  general  head  which  is  the 
common  property  of  all. 

From  their  composition,  one  may  well  surmise  that 
they  are  hardly  fit  to  be  used  in  distemper  or  water-color 
painting  owing  to  the  liability  of  their  chromic  constituents 
of  losing  their  oxygen  and  of  thus  becoming  changed  into 
the  lower  oxide  of  chromium,  which  is  greenish.  The  lead 
also  is  subject  to  the  attacks  of  sulphureted-hydrogen 
gases  which  turn  it  into  a  black  sulphide.  It  must  be 
easily  seen  by  any  one  that  great  risks  are  run  when  they 
are  used  in  water  colors  for  interiors,  about  the  only 
place  where  water  colors  can  be  used.  When  used  in  oil, 
they  are  protected  to  some  extent  by  the  linseed  oil  with 
which  they  are  mixed,  but  in  water  colors  there  is  no 
protection  whatever  against  deleterious  attacks.  - 

In  oil,  however,  there  are  but  few  colors  which  the 
painter  or  decorator  could  find  more  useful  than  the 
chrome  yellows.  While  not  absolutely  unfading  when 
mixed  with  oil  or  varnish,  in  those  vehicles  the  color 
remains  a  reasonably  long  time  before  changing  to  such 
a  degree  as  to  be  disagreeably  noticeable. 

The  range  of  tints  obtainable  from  them  covers  the 
whole  field  of  yellows  and  red  yellows,  which  are  easily 
made  and  at  a  very  moderate  cost. 

There  is  one  thing  that  is  sure :  There  is  nothing  in  the 
whole  field  of  pigment  that  would  replace  them,  let  them 
be  good  or  bad.  It  is  true  that  some  very  few  tones  could 
be  made  from  combinations  of  other  pigments,  but  at  a 
greatly  increased  cost  only,  almost  prohibitive  for  general 
house  painting,  and  nearly  all  these  substitutes  would  be 
much  more  subject  to  fading  than  the  chrome  yellow  itself. 
With  all  their  defects,  —  and  it  is  admitted  that  they  have 
many,  —  they  stand  high  above  every  other  pigment  pro- 
ducing the  same  range  of  color.  They  will  continue  to  be 


78  MODERN  PIGMENTS 

used  until  something  better  is  discovered  to  replace 
them. 

There  are  many  fancily  named  yellow  colors  upon  the 
market,  usually  with  a  proprietary  name.  They  are 
mainly  prepared  for  the  carriage  trade.  Most  of  them 
are  chrome  yellows  of  peculiar  shades. 

The  fancy  names  sometimes  mislead  the  uninitiated  into 
the  belief  that  they  are  not  chrome  yellows.  This  belief 
is  dangerous,  as  it  may  lead  one  into  using  those  yellows 
upon  work  where  chrome  yellow  should  not  be  employed, 
the  workman  thinking  that  they  are  not  subject  to  the 
same  vicissitudes.  With  a  knowledge  of  their  real  char- 
acter, such  mistakes  need  not  occur. 

Chrome  yellows  are  extensively  used  for  all  kinds  of 
painting.  The  carriage,  car,  and  implement  trades  use 
them  in  enormous  quantities  as  well  as  the  house  painter. 

Decorators  and  artists  are  the  ones  who  are  the  most 
likely  to  have  trouble  with  them.  They  are  the  only  ones 
who  need  have  any  misgivings  regarding  their  use.  They 
know  that  even  when  mixed  with  oil,  the  chrome  yellows 
are  not  to  be  depended  upon  for  use  in  interior  work. 
They  are  therefore  warned  to  be  shy  of  them,  substituting 
other  yellows  as  far  as  they  can. 

BARYTA  LEMON  YELLOW 

Properties  and  Uses 

This  is  a  distinct  color  from  lemon  chrome  yellow. 
It  contains  no  lead  in  its  composition,  baryta  being  the 
base  of  it.  It  is  by  far  the  most  permanent  form  of  that 
color. 

It  is  made  by  mixing  solutions  of  neutral  potassium 
chromate  and  of  barium  chlorite;  both  solutions  having 
previously  been  heated  to  100°  C.  It  precipitates  as  all 


YELLOW  PIGMENTS  79 

others  made  by  mixing  solutions  having  an  affinity  for 
each  other. 

Unlike  the  lead  chromates,  it  does  not  blacken  by  con- 
tact with  sulphureted-hydrogen  gases,  that  lurking 
enemy  of  interiors.  It  may  also  be  mixed  with  impunity 
with  any  of  the  other  permanent  pigments. 

This  yellow  is  of  great  use  to  decorators  and  artists, 
more  so  to  them  than  to  the  general  house  or  carriage 
painter,  because  it  has  not  so  much  opacity  in  oil  as  the 
chrome  yellows,  on  account  of  the  transparency  of  its 
base. 

It  possesses  one  of  the  defects  which  is  also  common 
to  the  chromates  of  lead.  It  loses  some  of  its  chromic 
oxide  and  becomes  greenish  in  hue. 

Adulteration  in  Chrome  Yellows 

To  detect  adulteration  in  chrome  yellow  is  an  easy 
thing.  It  can  be  done  by  a  very  simple  operation,  which 
while  it  is  not  a  scientific  one,  and  while  it  gives  no  indi- 
cation of  the  nature  of  the  adulterant,  is  nevertheless 
very  effective.  By  its  use,  any  one  can  readily  deter- 
mine for  himself  whether  a  given  sample  of  chrome  yellow 
is  pure  or  not.  This,  after  all,  is  all  that  either  a  painter 
or  a  dealer  cares  to  know  about  a  color  anyway.  The 
test  gives  approximately  the  percentage  of  adulterant 
contained  in  the  color  under  examination.  Its  lameness 
is  that  the  nature  of  the  adulterant  is  not  revealed.  That 
requires  a  chemical  analysis.  As  this  test  is  applicable 
to  many  other  pigments,  especially  to  all  made  from  chem- 
icals and  which  possess  a  recognized  standard  of  purity 
and  composition,  and  as  it  is  also,  in  part  at  least,  appli- 
cable to  many  of  the  earth  colors  in  so  far  as  it  will  fre- 
quently help  one  in  determining  the  value  of  these,  the 
manner  of  making  this  test  is  minutely  described,  so  that 


80  MODERN  PIGMENTS 

hereafter,  when  there  may  be  occasions  for  reference  to  be 
made  to  it,  the  reader  can  turn  back  to  the  explanation 
given  here,  should  he  require  to  have  his  memory 
freshened  up  as  to  the  "modus  operandi"  of  making  the  test. 

The  Scale  Test  for  Adulterants  in  Colors 

As  a  detector  for  adulteration  in  colors,  the  test  which 
is  about  to  be  described  is  applicable  in  full  only  to  those 
manufactured  in  color  works  from  well-known  formulas, 
and  which,  if  pure,  should  contain  a  known  amount  of 
coloring  matter.  That  is  what  gives  them  their  com- 
mercial value.  This  test  only  becomes  a  side  issue  with 
colors  whose  chief  value  consists  in  their  fine 
tone  and  their  brilliancy,  as  with  most  of  the  earth 
colors.  Even  with  these,  the  test  will  serve  to  deter- 
mine which  is  the  more  valuable  between  two 
samples  of  equal  tone  and  brilliancy  in  determining 
that  containing  the  greatest  quantity  of  coloring 
matter. 

Every  one  interested  in  colors,  be  he  dealer  or  painter, 
should  possess  a  pair  of  fine  scales  for  testing.  These 
should  be  very  sensitive  ones,  very  accurate,  and  able  to 
weigh  with  precision  as  small  a  portion  as  a  quarter  of  a 
grain,  or  at  least  a  centigram.  Such  scales  need  not 
necessarily  be  expensive.  The  knocked-down  army 
surgeon  pocket  scale  is  good  enough,  if  one  does  not  care 
for  style.  That  has  a  little  flat  box  with  a  drawer 
fitting  inside.  This  box  serves  as  a  pedestal,  and  the 
drawer  as  a  receptacle  into  which  is  packed  away  the 
standard  that  screws  into  the  pedestal  and  across  which 
the  arm  of  the  scale  is  pivoted  and  supports  the  two 
platters,  pans,  or  balances  which  receive  the  substances 
to  be  weighed.  They  can  be  put  up  and  taken  apart 
in  two  minutes,  and  will  answer  every  purpose. 


YELLOW  PIGMENTS  81 

The  testing  in  substance  is  done  in  the  following  man- 
ner. Two  samples  of  a  given  color  are  procured  —  one  of 
which  is  of  known  purity,  to  serve  as  the  standard  in 
judging  the  others.  A  very  good  plan  is  to  take  tubes 
of,  say,  Windsor  and  Newton's  artists'  colors,  or  any  other 
make  whose  purity  is  as  well  established.  The  above 
firm's  make  is  named  because  they  are  universally  known 
and  acknowledged  as  standard  in  both  quality  and  purity. 
A  sample  tube  of  all  the  principal  colors  should  be  found 
upon  the  shelf  of  every  paint  shop  and  of  every  paint 
dealer.  The  cost  is  very  moderate. 

It  stands  to  reason,  that  if  a  person  should  take,  say, 
one  pound  of  color  ground  in  oil,  and  add  thereto  twenty- 
five  or  fifty  pounds  of  white  lead,  and  that  after  triturat- 
ing them  properly  they  will  make  a  tint  that  should  be 
equal  in  strength  or  depth  of  tone  and  in  its  quality  to 
any  other  sample  or  samples  tested  with  it  if  those  sam- 
ples have  been  weighed  out  and  treated  in  exactly  the 
same  way,  they  will  do  so  if  they  are  pure  and  unadul- 
terated. If,  on  the  other  hand,  some  of  the  samples  do 
not  give  as  deep  a  tint  as  the  standard  color,  it  follows 
necessarily  that  there  must  be  deficiency  in  coloring 
matter. 

It  is  impossible  to  determine  to  a  fraction  the  amount 
of  adulteration  contained  in  the  weaker  pigment,  but  one 
can  make  a  very  close  guess  of  it  in  this  way : 

Add  enough  white  lead  to  the  sample  which  is  the 
strongest  in  coloring  matter  so  that  its  tint  will  be 
reduced  to  the  same  shade  as  that  of  the  weakest;  then 
reweigh  and  note  the  variation.  Thus,  if  one  pound  of 
a  certain  pigment  tints  twenty-five  pounds  of  white  lead 
to  a  given  shade,  and  in  the  other,  the  one  pound  of  the 
same  color  has  been  able  to  tint  thirty-seven  and  a  half 
pounds  of  the  white  lead  to  the  same  shade  as  the  other 


82  MODERN  PIGMENTS 

has  —  then  the  first  must  have  been  adulterated  with 
50  per  cent  of  something  that  was  not  coloring  matter. 
If,  instead  of  thirty-seven  and  a  half  pounds,  it  had 
been  able  to  tint  fifty  pounds  of  white  lead  to  that 
same  tint,  then  the  adulterant  put  into  the  color  would 
be  equal  to  100  per  cent.  In  other  words,  the 
sample  contains  one  half  pound  of  true  color  and  one 
half  pound  of  adulterating  material,  so  that  for  tinting 
purposes  it  is  only  worth  one  half  as  much  as  the 
stronger  one. 

Some  may  think  that  the  above  is  an  extravagant 
statement  to  make,  even  as  an  illustration  to  show  how 
the  test  works,  but  it  will  be  found  very  much  below 
the  truth.  This  is  especially  so  in  the  higher-priced 
pigments  and  in  those  possessing  great  strength  of 
coloring  matter. 

In  making  tests,  there  is  no  need  of  using  any  such 
quantity  of  color  and  lead  as  was  stated  in  the  illustration. 
One  grain  in  weight  is  as  good  as  one  pound,  or  even 
better.  No  weights  need  be  used,  as  a  bit  of  coloring 
matter  the  size  of  a  pea  can  be  put  upon  one  of  the  plat- 
ters, while  another  bit  of  color  can  be  placed  upon  the 
other,  and  added  to  or  subtracted  from  until  they  balance 
evenly.  Each  of  the  colors  to  be  tested  should  be  put 
upon  a  little  piece  of  paraffined  paper  about  a  square 
inch  in  area.  That  paper  will  not  absorb  any  of  the  color 
or  oil,  which  can  be  wiped  clean  off  of  it.  For  accurate 
testing,  it  is  better  to  weigh  the  colors  separately  in  cen- 
tigrams or  grains.  Next  proceed  to  equal  quantities  of 
white  lead  of  same  consistency,  placing  that  also  upon 
squares  of  paraffined  paper,  but  larger  than  recommended 
for  colors,  so  as  to  accommodate  the  larger  bulk  of  the 
lead.  These  are  placed  upon  the  platters  and  balanced 
in  the  same  manner  as  for  the  colors  by  either  adding 


YELLOW  PIGMENTS  83 

or  subtracting;  or,  if  perfect  accuracy  is  desired,  weigh  out 
twenty-five  or  fifty  grain  packages  of  white  lead,  one 
each  for  each  color  being  tested. 

Have  several  pieces  of  glass  ready  which  have  been 
properly  cleaned,  and  upon  one  of  these  place  the  first 
sample,  which  should  be  the  standard  color.  Add  to  this 
one  of  the  packages  of  white  lead  previously  weighed  out. 
Triturate  the  color  with  the  lead  until  the  tint  is  uni- 
form all  through,  using  a  palette  knife  for  that  purpose; 
add  a  given  number  of  drops  of  oil  if  needed  to  help  the 
mixing,  then  set  it  aside. 

Proceed  to  treat  the  next  sample  in  precisely  the  same 
way,  and  stand  that  aside  too.  If  more  than  two  samples 
are  being  tested,  keep  on  treating  each  in  the  manner 
described. 

Now  compare  each  sample  with  the  tint  made  by  the 
standard  color  and  note  the  differences.  If  each  shows 
about  the  same  strength  in  their  tints,  well  and  good;  the 
colors  are  pure.  If,  on  the  other  hand,  one  or  more  do  not 
come  up  to  the  tint  of  the  standard,  there  is  something 
wrong  with  them.  By  adding  enough  white  lead  to  the 
standard  tint  to  bring  it  down  to  the  tint  of  the  next 
strongest  sample  being  tested,  and  weighing  each,  the 
difference  between  them  will  give  the  quantity  of  adul- 
teration contained  in  the  sample. 

If  more  samples  than  one  are  being  tested  at  the  same 
time,  proceed  to  add  more  white  lead  to  the  standard 
color;  continue  adding  white  lead  to  the  standard  to 
bring  it  down  to  the  tint  of  the  next  sample  in  strength, 
weighing  each  time  and  noting  the  difference,  and  continue 
doing  so  in  like  manner  until  the  standard  has  been 
reduced  to  the  tint  of  the  last  or  weakest  in  the  lot.  This 
will  give  the  relative  value  that  each  bears  to  that  of  the 
standard  used. 


84  MODERN  PIGMENTS 

Thus  if  the  standard  color  is  capable  of  producing  a 
tint  from  one  grain  of  color  added  to  two  hundred  grains 
of  white  lead  equal  to  that  which  sample  1  does  from  one 
grain  of  color  to  one  hundred  grains  of  white  lead,  and  as 
sample  2  does  with  fifty  grains  of  lead,  then  if  the  stand- 
ard color  can  be  bought  for  twenty  cents  per  pound, 
sample  1  is  worth,  proportionately,  ten  cents.  Sample  2 
is  only  worth  five  cents  per  pound,  because  No.  1  contains 
only  fifty  per  cent  of  the  coloring  matter  as  compared  to 
the  standard,  while  No.  2  carries  only  twenty-five  per  cent 
of  it. 

In  the  testing  of  chrome  yellows,  samples  of  different 
tones  should  never  be  tested  together, —  for  instance,  a 
very  light  lemon  yellow  against  a  very  dark  one,  or  a 
lemon  chrome  against  a  medium  or  an  orange  chrome,  or 
vice  versa.  The  tints  made  will  be  so  much  different 
that  it  would  be  very  hard  if  not  impossible  to  judge  the 
results  correctly  when  placed  side  by  side. 

This  test  usually  brings  out  other  valuable  points,  i.e., 
the  quality  of  the  tints  made  from  two  or  more  given 
samples.  A  medium  chrome  yellow  may  be  nearly  pure, 
but  it  may  be  very  poor.  Therefore,  if  the  tint  obtained 
from  it  is  muddy,  and  that  from  the  standard  is  bright, 
clear,  and  pure-toned,  it  follows  that  the  muddy  sample 
was  a  badly  made  chrome  yellow,  and  that,  notwithstanding 
its  purity,  it  may  possibly  be  of  less  value  than  one  which 
has  been  adulterated  but  which  is  of  good  tone  and  well 
made.  This  is  a  test  of  quality  which  is  brought  out  inci- 
dentally by  the  use  of  the  scale  test. 

The  testing  of  the  quality  of  colors  does  not  require 
the  scale  test,  however,  as  one  can  ascertain  that  by  the 
eye  alone.  All  that  is  required  is  to  mix  some  of  the 
color  with  white  lead  to'  make  a  light  tint  of  it.  The  tint 
will  speak  for  itself.  The  tone  of  some  samples  of  chrome 


YELLOW  PIGMENTS  85 

yellow  may  be  so  poor  that  the  quality  can  be  determined 
without  disturbing  it  or  even  taking  it  out  of  the  can.  As 
occasionally  it  may  belie  its  looks,  it  is  safer  to  add  some 
white  lead.  Then  there  can  be  no  doubts  left  in  one's 
mind. 

Color  tests  made  in  the  above  manner  are  very  simple 
and  convincing ;  and  the  painters  or  dealers  who  make  a 
start  in  testing  the  material  they  use  or  sell,  hardly  ever 
quit  making  a  regular  use  of  it,  thereby  gaining  an  expe- 
rience in  judging  of  colors  and  their  values  that  will  be 
very  profitable  to  them  in  after  life. 


CHAPTER  VII 

t 

YELLOW  PIGMENTS  (Continued) 
GAMBOGE 

Properties  and  Uses 

GAMBOGE  is  seldom  if  ever  employed  by  the  house 
painter,  but  is  still  used  by  a  few  decorators  and  artists. 
Its  chief  value  is  as  a  glazing  color;  in  reality  it  cannot  be 
used  for  any  other  purpose;  some  few  carriage  painters  who 
do  fancy  colored  painting  use  it  to  obtain  certain  effects. 

Gamboge  is  of  vegetable  origin;  being  a  gum-resin.  It 
should  never  be  mixed  with  other  pigments  containing 
lime  or  alkali  in  any  form;  they  would  surely  darken. 

It  cannot  be  safely  used  as  a  distemper  color,  as  it 
fades  rapidly  upon  exposure  to  the  air  and  the  sun's  rays. 
Its  use  even  in  oil  is  questionable,  but  it  is  fairly  permanent 
when  well  protected  by  varnish. 

Its  chief  use  to  artists  is  in  the  peculiar  shades  of  green 
combined  with  indigo  or  Prussian  blue. 

The  paint  world  is  likely  to  keep  moving  on  a  long  time 
after  it  has  been  discarded,  as  its  place  can  be  advan- 
tageously taken  by  Indian  yellow  or  aureolin. 

AUREOLIN,  OR  COBALT  YELLOW 

Properties  and  Uses 

This  is  another  yellow  pigment  which  will  hardly  ever 
trouble  the  ordinary  house  painter.  A  few  decorators  use 

86 


YELLOW  PIGMENTS  87 

it  sparingly.  It  is  used  principally  by  artists  in  water- 
color  work.  It  is  transparent  and  rich-toned,  and  is 
superior  to  gamboge  for  glazing  purposes. 

It  is  a  non-drying  color  in  oil.  When  prepared  for  use 
in  that  vehicle  it  will  prove  more  or  less  troublesome.  If 
it  can  ever  be  prepared  in  such  a  way  as  to  make  it  part 
with  its  water  of  hydration,  —  in  other  words,  rendered 
anhydrous  at  a  reasonable  cost,  —  it  may  then  become  a 
very  popular  color  not  only  among  decorators  but  for 
carriage  and  the  allied  trades  as  well  as  for  any  other 
kind  of  painting.  As  it  is  now  in  its  hydrated  state,  it 
soon  loses  its  rich  tone  and  assumes  a  dirty  appearance. 
Hydrochloric  and  nitric  acids  do  not  seem  to  affect 
it  to  any  extent,  but  ammoniacum  sulphide  destroys 
its  color  at  once,  and  sulphureted  hydrogen  gases  soon 
darken  it. 

The  future  may  give  us  the  anhydrous  aureolin  at  a 
reasonable  cost.  When  this  is  accomplished,  it  will  be  a 
great  addition  to  the  list  of  yellow  pigments.  In  that 
form,  it  dries  readily  when  mixed  with  a  siccative  oil,  and 
that  is  the  form  in  which  artists  now  use  it  for  oil  paint- 
ing. As  they  use  it  in  small  quantities,  it  does  not  make 
such  a  big  hole  in  their  bank  account  as  it  would  were  they 
to  use  it  in  quantities  as  the  house  painter  or  decorator 
would. 

INDIAN  YELLOW 

Properties  and  Uses 

This  pigment  is  of  animal  derivation,  but  in  reality  it 
is  of  vegetable  origin  obtained  through  animal  agency; 
it  is  found  in  their  urine.  In  Bengal,  cows  are  fed  upon 
mango  leaves,  and  the  urine  of  cows  so  fed  becomes  im- 
pregnated with  the  coloring  matter  which  forms  Indian 
yellow. 


88  MODERN  PIGMENTS 

Church  says  of  it:  "It  generally  occurs  in  the  bazars  of 
the  Punjaub  in  the  form  of  large  balls  having  an  offensive, 
urinous  odor."  Indian  yellow  is  an  impure  salt  of 
(magnesium)  euxanthic  acid.  The  essential  part  of  it  is  a 
compound  containing  4.5  per  cent  magnesia,  18.7  per 
cent  water,  78.7  per  cent  euxanthic  anhydride;  but  this 
substance  is  always  associated  with  various  impurities 
both  mineral  and  organic,  even  in  the  most  carefully 
purified  samples  of  prepared  Indian  yellow.  The  pure 
magnesium  euxanthate  is  represented  by  the  formula 
C19  II16MgOn5H20. 

"  For  artistic  purposes  the  crude  imported  Indian 
yellow  is  thoroughly  powdered,  and  then  washed  with 
boiling  water  until  the  liquid  filtered  from  it  is  no  longer 
colored;  a  brown  impurity  and  much  of  the  evil  smell  are 
thus  removed.  The  color  of  the  washed  product  is 
enriched  by  leaving  it  in  contact  for  a  day  or  two  with 
a  saturated  solution  of  salammoniac  and  then  repeating 
the  treatment  with  hot  water.  Thus  prepared  and 
purified,  the  pigment  presents  a  translucent  orange  yellow 
of  great  depth  and  beauty.  Ground  in  oil,  some  specimens 
remain  practically  unchanged  even  after  long  exposure 
to  sunlight,  any  darkening  which  they  show  being  due  to 
either  imperfect  purification  or  to  change  in  the  associated 
oil.  Such  change  is  reduced  to  the  minimum  if  poppy- 
seed  oil  is  substituted  for  linseed  oil,  or  if  the  latter  be 
previously  treated  with  manganese  bo  rate." 

As  a  water  color,  Indian  yellow  is  also  very  useful.  It 
is  not  absolutely  permanent,  but  fairly  so  for  a  water- 
color  yellow.  Its  fading,  being  very  slow  and  gradual,  is 
not  noticed  readily. 

It  can  be  mixed  with  any  of  the  permanent  pigments, 
and  sulphurous  compounds  do  not  affect  it  injuriously. 
It  is  too  expensive  a  pigment  to  ever  become  extensively 


YELLOW  PIGMENTS  89 

used  by  ordinary  painters,  but  it  deserves  to  be  more 
than  it  is  by  decorators,  scenic  painters  and  artists, 
also  by  the  carriage  trade  as  a  glazing  color.  It  does 
all  that  gamboge  is  expected  to  do  for  that  purpose,  and 
much  more  in  that  it  remains  permanently. 

NAPLES  YELLOW 

History  and  Chemistry 

The  early  history  of  this  pigment  is  very  obscure.  It 
was  first  brought  «to  notice  in  a  commercial  way  by  the 
Italians,  and  imported  from  the  city  of  Naples  in  Italy 
into  England,  and  it  was  named  after  the  city  of  its 
exportation  by  the  English  importers.  The  Italians 
themselves  know  it  as  yellow  or  gialloline.  It  is  a 
compound  of  oxide  of  lead,  antimony  and  zinc.  Twelve 
parts  of  the  metallic  antimony  are  calcined  in  a 
reverbatory  furnace  with  eight  parts  of  red  lead  and 
four  parts  of  the  zinc.  These  mixed  oxides  after  being 
well  rubbed  together  are  fused,  and  the  mass  broken  into 
a  fine  powder. 

The  hue  is  rich,  fresh,  and  brilliant.  There  is  a  con- 
siderable quantity  of  this  yellow  placed  upon  the  market 
that  is  made  simply  by  mixing  cadmium  yellow  or  a  deep 
cadmium  with  the  white  oxide  of  zinc.  This,  while  it 
makes  a  good  imitation  of  Naples  yellow,  is  not  it,  for 
all  that  it  may  look  like  it. 

While  it  is  only  of  comparatively  recent  date  that  it 
has  come  back  to  us,  the  first  notes  of  its  appearance  only 
dating  back  to  the  middle  of  the  sixteenth  century, 
it  was  known  to  the  ancients  for  many  centuries  previous 
to  that  time.  It  was  used  in  the  enameling  of  brick  in 
Babylon  700  years  B.C.,  and  the  Persians  used  it  also 
in  the  enameling  of  their  pottery. 


90  MODERN  PIGMENTS 

It  has  been  used  extensively  by  artists,  decorators,  sign 
and  carriage  painters,  and  is  still  used  to  a  certain  extent 
by  some  of  all  these  to-day,  but  not  nearly  to  the  same 
extent  as  it  was  fifty  years  ago.  The  chrome  yellows 
have  made  quite  an  inroad  upon  its  use,  and  have  dis- 
placed Naples  yellow  in  many  shops. 

Properties  and  Uses 

Naples  yellow  is  fairly  permanent,  but,  like  all  com- 
pounds containing  lead,  it  is  blackened  by  sulphureted - 
hydrogen  gases.  It  is  also  darkened  by  contact  with 
iron,  zinc,  pewter,  tin,  and  many  more  metals,  to  the 
extent  that  even  an  iron  palette  knife  should  never  be 
used  in  triturating  it,  but  a  bone  one  should  always  be 
employed  for  this  purpose. 

Naples  yellow  should  never  be  used  in  combination 
with  certain  organic  pigments  as  cochineal,  the  various 
yellow  lakes,  indigo,  etc.  Naples  yellow  is  worthless  as 
a  water  color,  as  it  is  very  fugitive  when  left  unprotected 
by  the  enamel  formed  by  the  drying  of  linseed  oil  or 
varnishes. 

It  is  gradually  becoming  displaced  by  the  chrome 
yellows  and  ochers,  or  combinations  of  these  two,  and 
with  no  serious  loss.  The  Naples  yellow  tone  can  be 
readily  imitated;  and  in  this  one  instance  at  least  the 
imitation  is  superior  to  the  original,  —  it  is  more  perma- 
nent. 

DUTCH  PINK 

Character  and  Preparation 

Dutch  pink  has  many  synonyms,  i.e.,  yellow  lake, 
Italian  lake,  quercitron  lake,  brown  lake,  yellow 
madder,  and  a  host  of  others  under  which  it  is  known  in 
various  sections,  especially  in  England,  where  it  is 


YELLOW  PIGMENTS  91 

unknown  under  the  American  cognomen  of  Dutch  pink. 
As  under  this  name  only  is  this  pigment  listed  in  pigment 
catalogues  in  the  United  States,  and  as  this  is  recognized 
by  all  color  makers  in  their  price  lists,  the  name  is  used 
here  in  preference  to  any  of  the  synonyms.  Why 
it  should  be  called  a  pink  (?)  when  it  is  not  a  pink, 
but  a  yellow,  is  one  of  the  conundrums  that  must 
be  passed  around  to  some  one  else  for  a  satisfactory 
explanation. 

Dutch  pink  is  of  vegetable  origin,  and  it  can  be  and  has 
been  prepared  from  various  sources,  but  it  is  now  chiefly 
derived  from  quercitron,  a  product  extracted  from  oak 
bark.  Our  black  and  red  oaks  contain  the  greatest  per- 
centage of  it,  although  it  can  be  obtained  from  the  bark 
of  white  oak  also. 

A  decoction  of  the  bark  is  made  by  boiling,  and  the 
quercitron  is  precipitated  by  pouring  into  it  while  hot 
a  solution  of  alum  and  dilute  ammonia. 

A  richer-toned  pigment  is  produced  by  using  dilute 
boiling  sulphuric  acid  instead  of  water  in  extracting  it 
either  from  the  ground  bark  or  alburnum. 

In  former  days  much  of  the  Dutch  pink  was  obtained 
from  various  species  of  buckthorn  and  of  the  Rhamus 
family  of  shrubs. 

Properties  and  Uses 

It  is  possible  that  the  variety  of  names  under  which 
Dutch  pink  is  known  may  have  been  given  to  the  various 
extracts  at  some  time  or  other  to  note  some  slight  varia- 
tion of  tone  in  them.  This  is  more  than  doubtful,  as  it 
is  next  to  impossible  to  ever  find  any  two  lots  of  it  that 
are  just  alike  in  this  respect.  It  is  useless  to  keep  up  a 
confusing  nomenclature,  and  all  lakes  of  the  same  extrac- 
tion should  be  classed  together  and  known  by  one  name 


92  MODERN  PIGMENTS 

only.  When  an  Englishman  calls  for  any  of  the  above- 
named  lakes,  the  dealer  will  be  perfectly  safe  in  giving 
him  Dutch  pink  instead  of  them. 

Dutch  pink  has  but  little  permanency  when  used  in 
distemper  for  wall  coloring,  and  yet,  strange  to  say,  that 
is  the  purpose  for  which  it  is  mostly  used.  Why  that  is 
so  is  one  of  the  unsolvable  mysteries. 

Its  use  in  the  United  States  is  confined  to  a  few  sec- 
tions where  the  traditions  of  its  usage  have  been  handed 
down  and  inherited  without  the  worth  of  the  legacy 
having  been  investigated. 

In  oil  it  is  a  bad  drier,  and  while  it  is  more  permanent 
in  that  vehicle  than  in  distemper,  —  because  of  the  pre- 
serving influence  exerted  upon  it  by  the  linseed  oil,  —  it 
is  insufficiently  so,  and  there  is  no  need  of  one  taking 
unnecessary  risks  by  using  it.  As  a  glazing  color  it  is 
all  right  while  it  lasts,  and  it  is  used  for  that  purpose  in 
some  carriage  shops. 

CADMIUM  YELLOW 

Chemistry,  Properties,  and  Uses 

This  pigment  is  chiefly  useful  to  the  artist  and  to  the 
decorator.  When  properly  prepared  it  is  fairly  perma- 
nent, but  as  its  cost  is  relatively  high  and  must  ever 
remain  so,  for  this  reason  if  for  no  other  its  use  will  never 
become  popular  with  the  house  painter.  As  its  name 
indicates,  it  is  a  product  of  the  metal  cadmium,  a  near 
relative  of  zinc.  It  is  a  sulphide  of  cadmium.  The  pro- 
cess required  for  its  manufacture  and  preparation  is 
too  intricate  and  too  lengthy  to  relate  in  a  treatise 
of  this  kind,  however  instructive  it  might  be.  Its  use 
is  too  limited  to  warrant  giving  it  the  necessary  space. 
It  runs  from  a  yellow  with  a  slight  orange  streak  in  it  to 


YELLOW  PIGMENTS  93 

all  the  intervening  shades  from  the  lightest  to  the 
deepest  orange. 

It  possesses  some  very  good  traits.  One  is  that  of 
preventing  the  injurious  action  of  sulphureted-hydrogen 
gases  upon  white  lead  when  it  is  mixed  with  that. 

On  the  contrary,  again,  such  colors  as  Paris  green  are 
ruined  by  contact  with  it,  and  so  are  all  others  which  are 
incompatible  with  a  sulphide. 

The  cadmium  yellows  work  well  in  either  oil  or  dis- 
temper, and  make  beautiful  tints  with  white  lead.  Some 
of  these  shades  resemble  true  Naples  yellow,  and  as  they 
are  more  permanent,  they  are  often  substituted  for  it. 
When  cadmium  yellow  is  used  in  oil,  this  should  be  made 
siccative  by  the  addition  of  driers. 

It  is,  therefore,  chiefly  used  by  decorators  for  interior 
work.  This  is  more  liable  to  attacks  of  sulphureted- 
hydrogen  gases  than  outside  painting,  and  as  the  chrome 
yellows  are  badly  affected  by  them,  and  therefore  unsafe 
to  use,  cadmium  yellow's  chief  utility  is  to  replace  them 
under  these  conditions. 

KING'S  YELLOW  (ORPIMENT) 

Chemistry  and  Characteristics 

This  pigment  is  the  yellow  arsenic  sulphide,  and  on 
account  of  its  poisonous  character  should  be  discarded. 

The  only  excuse  for  listing  it  at  all  is  that,  under  its 
heading,  a  note  of  warning  might  be  given  against  its 
use.  It  is  listed  in  some  of  the  artists'  goods  catalogues, 
and  some  reference  is  made  to  it  in  some  of  the  past 
paint  literature. 

Under  its  best  aspects  it  has  little  to  recommend  it, 
and  when  its  poisonous  character  is  taken  into  account, 
no  one  need  have  anything  to  do  with  it.  At  best,  it  is 


94  MODERN  PIGMENTS 

quickly  destroyed  by  light,  and  while  it  possesses  a  beau- 
tiful hue,  that  fades  away  so  quickly  as  to  render  it 
worthless. 

It  was  used  rather  extensively  at  one  time,  especially 
in  the  latter  part  of  the  eighteenth  century  and  at  the 
beginning  of  the  nineteenth.  It  has  all  disappeared  from 
the  paintings  of  that  period  which  have  been  preserved, 
and  it  is  but  seldom  used  to-day  even  by  artists. 

The  above  ends  the  list  of  yellow  pigments.  It  is  true 
a  few  others  are  sometimes  found  listed  in  artists'  cata- 
logues, such  as  Mars  yellow,  etc.,  but  a  close  inquiry  will 
develop  that  they  are  simply  ochers  or  compounds  of 
colors  which  have  been  described. 

The  endeavor  should  be  made  to  keep  the  list  of  pigments 
to  the  least  possible  number  and  to  simplify  the  nomen- 
clature by  eliminating  from  the  list  all  pigments  of  the 
same  nature  sold  under  various  names,  thus  creating  a 
false  impression  in  the  minds  of  many  that  they  may 
have  different  properties. 

Many  of  the  yellows  which  have  received  a  description 
in  this  treatise  will  be  found  of  little  benefit  to  the  gen- 
eral painter,  but  most  are  of  use  in  certain  special  kinds 
of  work  which  are  named.  The  very  knowledge  that 
they  are  not  adapted  to  his  work  is  of  value,  as  it  may 
save  him  money  in  the  making  of  useless  experiments. 
The  aim  has  been  to  give  warning  of  all  the  defects  as 
freely  as  the  giving  of  praise  to  the  good  qualities  of  each 
when  that  was  really  deserved. 


CHAPTER  VIII 

RED   PIGMENTS 

VERMILION 

History  and  Provenance 

QUICKSILVER  VERMILION  is  usually  understood  when  the 
word  vermilion  pure  and  simple  is  used  alone.  All  others 
have  some  descriptive  name  added  to  indicate  their 
character. 

Quicksilver  vermilion  is  commonly  listed  as  English 
Vermilion,  and  the  name  has  come  to  have  that  signifi- 
cation to  the  paint  trade  of  the  United  States. 

Vermilion  is  found  as  a  natural  product  in  the  shape  of 
and  under  the  name  of  cinnabar  in  various  parts  of  the 
world.  It  is  most  abundant  in  China,  and  has  been  found 
and  used  in  that  country  from  time  immemorial.  In  America 
it  is  also  found  plentifully  in  the  New  Almaden  mines  of 
California.  In  Spain,  in  the  old  Almaden;  in  short, 
wherever  quicksilver  is  mined,  there  it  is  usually  found. 

It  is  frequently  obtained  in  masses  which  vary  very 
much  in  color,  ranging  from  a  light  crimson  through  the 
scarlet  red  range  of  shades  to  a  dark  slate  gray.  These 
masses  after  having  been  powdered  become  scarlets  or 
reds  of  various  hues. 

The  native  vermilion  or  cinnabar  is  usually  singularly 
pure  and  free  from  foreign  matter,  and  the  impurities 
seldom  amount  to  as  much  as  one  per  cent  of  its  weight. 
It  is  friable,  readily  pulverized. 

95 


96  MODERN  PIGMENTS 

Chemistry  and  Manufacture 

Cinnabar  is  a  native  sulphuret  of  mercury,  and  it  is 
composed  of  86  parts  of  mercury  united  to  14  parts  of 
sulphur. 

It  is  most  probable  that  it  was  used  at  very  remote 
periods  in  such  decorations  and  art  as  then  existed. 
Theophrastus  names  two  varieties  of  cinnabar  as  being 
known  to  the  Greeks.  Pliny  and  Vitruvius  also  mention 
it  in  their  writings. 

Vermilion  can  be  made  artificially  by  following  the 
formula  nature  has  adopted  to  produce  the  native  cinna- 
bar. The  vermilion  of  commerce  is  nearly  all  made 
artificially. 

The  process  of  manufacturing  it,  while  it  may  be  called 
a  very  simple  one,  becomes  rather  complex  before  the 
end  is  reached. 

The  combination  of  quicksilver  and  sulphur  is  readily 
accomplished,  it  is  true,  but  the  result  is  a  black  mass 
known  as  Ethiops.  This  is  the  black  sulphuret,  and  it  is 
identical  in  chemical  composition  to  the  red,  with  this 
difference  —  that  the  black  is  amorphous,  while  the  red  is 
crystalline. 

There  are  two  processes  of  manufacturing  vermilion 
artificially :  one  is  known  as  the  dry,  and  the  other  as  the 
wet. 

In  the  dry  method  of  manufacturing  it,  the  mercury 
and  sulphur  in  the  proportion  of  21  parts  of  the  former  to 
4  of  the  latter  are  agitated  and  mixed  in  a  revolving 
cylinder.  The  resulting  black  ethiops  is  then  submitted 
to  a  process  of  sublimation  in  vertical  cylinders,  over 
which  are  placed  connecting  receivers.  Upon  being 
heated  sufficiently,  the  sulphuret  of  mercury  sublimes 
as  cinnabar  near  the  retort's  heads;  the  finer  quality  is 


RED  PIGMENTS  97 

found  the  farthest  away,  and  the  poorest  the  nearest,  as 
that  contains  a  quantity  of  free  sulphur.  It  is  afterward 
separated  into  various  grades. 

The  vermilion  is  mixed  with  water  to  a  stiff  paste,  and 
thinned  with  a  solution  of  caustic  potash  and  nitric  acid, 
and  thoroughly  washed  with  boiling  water.  There  are 
other  processes  of  manufacturing  vermilion,  but  they 
differ  but  little  in  their  essentials  from  the  above,  and 
therefore  will  not  be  discussed.  All  have  the  same  object, 
—  the  conversion  of  the  black  amorphous  sulphuret  into 
the  red  crystalline  form  by  sublimation.  Some  add  one 
per  cent  of  sulphide  of  antimony  with  a  view  of  enhanc- 
ing the  beauty  of  the  product. 

By  the  wet  method,  the  processes  are  much  simpler, 
and  there  are  a  number  of  different  ones  in  use.  The 
simplest  is  that  of  Bucholz:  Take  four  parts  of  mercury 
and  one  part  of  sulphur,  which  are  digested  together  in 
six  parts  of  water.  Potash  is  added  as  required.  The 
longer  the  heat  is  continued,  the  stronger  and  more  car- 
mine will  be  the  product.  When  the  desired  color  has 
been  produced,  the  vermilion  is  thrown  into  a  vessel  of 
water  and  washed  until  all  the  sulphuret  of  potash  has 
been  removed.  The  color  of  vermilion  is  not  changed 
when  moistened  with  nitric  acid. 

Carmine  is  sometimes  added  to  the  crimson  varieties 
of  vermilion  to  enhance  the  tone.  The  Chinese  vermilions 
are  usually  of  that  shade.  They  are  frequently  adul- 
terated with  carmine.  It  can  easily  be  detected  by  putting 
a  small  pinch  of  it  upon  a  piece  of  blotting  paper  and 
wetting  that  with  a  few  drops  of  strong  aqua  ammonia. 
If  adulterated,  a  crimson  stain  will  appear  upon  the  paper; 
otherwise  it  will  not  be  affected. 

Vermilion  that  is  prepared  from  the  native  cinnabar 
is  said  to  be  more  permanent  than  that  which  is  made 


98  MODERN  PIGMENTS 

artificially,   but  one    should    not    adopt    the    statement 
implicitly. 

Characteristics  and  Uses 

When  vermilion  is  used  under  proper  conditions  it  is 
fairly  permanent,  otherwise  it  is  not. 

As  to  the  darkening  of  vermilion,  the  common  complaint 
made  against  it,  one  must  bear  in  mind  that  the  natural 
form  of  the  sulphuret  of  mercury  is  that  of  the  black 
ethiops  or  amorphous,  while  that  of  the  red  or  crystalline 
is  a  forced  one.  There  is  a  constant  return  from  the 
crystalline  to  its  natural  amorphous  condition,  hence 
comes  the  gradual  darkening  of  this  beautiful  color  when 
left  to  the  direct  action  of  light  and  air.  Even  when  not 
directly  exposed  to  the  action  of  the  elements,  the  gradual 
change  takes  place,  but  in  a  much  slower  way. 

Vermilion  prepared  by  the  wet  process  is  usually  more 
crimson  than  that  made  by  the  dry,  and  this  is  more 
likely  to  fade  than  the  scarlet-toned  ones.  Another 
peculiarity  of  the  wet  process  and  of  all  crimsoned -toned 
vermilions  is  that  they  do  not  have  as  good  a  body  or  are 
not  so  opaque  as  those  of  a  scarlet  tone.  Another  pecu- 
liarity of  vermilion  is  that  the  finer  it  is  ground,  the  paler 
it  becomes  and  the  quicker  it  will  fade.  As  a  water  color, 
when  it  is  left  unprotected  from  the  influences  of  air  and 
light,  vermilion  is  absolutely  unreliable  under  such  cir- 
cumstances. 

In  oil  or  varnish,  it  is  fairly  permanent ;  and  when  the 
painting  has  been  done  on  a  proper  ground  with  the  right 
vehicles,  and  afterward  well  varnished  over,  it  will  not 
change  readily,  and  may  be  called  "  unfading,"  com- 
paratively so  at  least. 

Linseed  oil  itself,  in  its  ordinary  condition,  is  not  a 
good  medium  for  it.  Gold  size,  japan,  or  a  good  varnish 


RED  PIGMENTS  99 

are  much  better  for  that  purpose.  This  is  the  principal 
reason  why  the  coach  and  car  painters  have  nothing  but 
praise  for  it  and  are  so  successful  in  its  use,  while  the  house 
painters,  who  are  used  to  mix  their  colors  differently,  and 
who  also  in  all  probability  are  not  so  familiar  with  the 
peculiarities  of  that  color,  usually  have  little  good  to  say 
of  it.  The  latter  bring  in  nearly  all  the  complaints  against 
it. 

The  genuine  simon-pure  vermilions  can  be  safely  used 
with  most  pigments.  It  is  only  when  they  contain  free 
sulphur,  as  in  the  lower  grades,  that  there  is  any  danger 
of  mixing  them  with  other  pigments. 

Vermilion,  owing  to  its  heavy  weight  or  density,  pre- 
cipitates readily  when  mixed  in  liquids,  therefore  it  is 
best  to  buy  it  in  a  dry  state.  It  is  found  ground  in  oil 
or  varnish  in  small  cans;  in  reality  it  is  not  ground  in 
them,  —  it  is  only  mixed  into  a  paste  with  the  liquids. 
This  the  painter  can  do  as  well  for  himself  at  the  shop 
without  any  waste,  as  he  need  mix  only  as  much  as  he 
wants.  The  grinding  would  destroy  the  color,  and  manu- 
facturers or  grinders  are  too  smart  to  want  to  do  that. 
The  coarser  the  atoms  of  vermilion,  the  richer  and 
more  brilliant  will  be  the  tone.  The  above  statement  is 
not  only  true  of  vermilion,  but  also  applies  to  all  colors 
having  a  crystalline  nature. 

A  crimson  vermilion  is  usually  more  transparent  than 
the  pale  or  finer  ones,  the  crystals  of  the  deep  crimson 
variety  being  coarser.  To  this  are  partly  due  its  greater 
transparency  and  brilliancy.  The  unbroken  crystals 
give  a  reflection  and  depth  to  the  finish  which  is  remark- 
ably beautiful.  It  is  not  so  fine  nor  as  opaque  as  the 
pale  vermilion,  but  richer  toned.  But  it  is  not  so  deficient 
or  transparent  but  that,  over  a  proper  ground,  it  will 
cover  well  in  one  coat. 


100  MODERN  PIGMENTS 

The  pale  varieties,  being  finer  and  more  opaque,  are  the 
ones  commonly  used  for  lining  or  striping,  and  the  only 
red  that  can  be  used  to  make  a  solid-looking  stripe  in  one 
coat  over  black. 

IMITATION  OR  VERMILION  REDS 

Manufacture  and  Preparation 

The  vermilion  reds,  as  the  imitation  vermilions  are 
now  called,  are  fast  encroaching  upon  the  domain  of  the 
genuine  or  English  vermilion,  as  quicksilver  vermilion 
is  usually  known  in  the  United  States.  It  is  really  won- 
derful to  note  how  much  progress  and  how  many  improve- 
ments have  been  made  in  the  manufacture  of  these  reds 
within  the  past  fifteen  years.  All  but  the  opacity  of  the 
genuine  pale  vermilion  has  been  attained  in  them  and 
reproduced  in  the  imitation.  In  some  respects,  as  in  per- 
manency, some  of  these  are  even  superior  to  the  genuine. 

This  progress  is  mainly  due  to  the  discoveries  in  the 
making  of  alizarin  and  other  high-grade  coal-tar  prod- 
ucts. Some  were  formerly  obtained  from  madder  root 
at  great  cost;  and  later  the  introduction  of  the  para- 
diazo  reds  has  completely  changed  the  output  in  that 
class  of  goods. 

A  short  review  will  be  made  of  the  different  grades  of 
vermilion  reds. 

Every  color  manufacturer  has  his  own  peculiar  way 
of  handling  or  preparing  vermilion  reds,  the  usefulness  of 
which  he  claims  to  be  "just  a  little  bit"  ahead  of 
that  of  his  competitors,  and  to  protect  which  he  gives 
to  his  products  a  proprietary  name. 

The  multitude  of  names  for  these  reds  has  been  the 
cause  of  no  end  of  worry  to  painters  and  paint  men  who 
are  not  familiar  with  them.  There  can  be  but  little  doubt 


RED  PIGMENTS  101 

that  in  the  recent  past,  when  every  thing  in  the  manu- 
facture of  vermilion  reds  was  new  and  really  in  an  ex- 
perimental stage,  there  was  considerable  difference  in  the 
output  of  the  different  manufacturers  of  these  reds.  Some 
seemed  to  have  the  coloring  matter  much  better  fixed 
than  others;  but  the  field  of  search  has  been  an  open  one 
to  all,  and  what  with  the  aid  of  chemistry  and  of  "catch- 
ing on"  combined,  the  competing  ones  have  not  been 
slow  to  note  any  improvement  in  the  other  fellow's  output 
nor  in  getting  acquainted  with  it  in  some  way  or  another. 
To-day  the  man  who  has  not  been  able  to  keep  up  his  end 
with  those  in  front,  has  had  to  abandon  the  field  or 
content  himself  with  the  making  of  inferior  goods  only, 
and  he  is  known  to  the  trade. 

The  result  of  this  competition  is  that  now  one  can 
safely  say  that  all  prominent  color  makers  make  good 
goods.  All  make  certain  lines  of  low-grade  goods,  as 
some  trades  want  them.  These  are  usually  colored  with 
a  cheap  aniline  color  thrown  upon  a  cheap  base.  But  as 
long  as  there  are  large  buyers  who  are  not  willing  to  pay 
more  for  a  vermilion  red  than  for  what  a  good  ocher  sells 
at,  they  will  be  catered  to.  These  cheap  reds  also  serve 
as  a  type  to  compare  the  crude  efforts  of  the  beginning 
with  what  has  now  been  achieved.  They  fairly  represent 
the  first  attempts  to  make  imitation  vermilion  some 
thirty  years  ago. 

The  vermilion  reds  are  all  made  upon  a  base  which  is 
dyed  with  a  coloring  agent.  The  coloring  agent  is  good 
or  poor,  an  expensive  or  a  cheap  coloring  coal-tar  dye 
which  may  be  worth  25  cents  or  $5  per  pound.  In  this 
as  well  as  in  every  other  instance,  the  better  dye  costs, 
the  most  money. 

White  lead  is  the  usual  base  taken  to  make  the  crimson 
varieties  of  vermilion  reds,  as  it  absorbs  a  much  larger 


102  MODERN  PIGMENTS 

proportion  of  the  dye  stuff  than  does  orange  mineral 
the  base  which  is  mostly  used  for  the  scarlet  varieties. 

The  two  above-named  bases  are  used  for  the  best 
grades  of  vermilion  reds  only,  and  intended  for  vermilions 
which  are  to  be  brushed  out  or  painted  over  by  hand  upon 
the  work.  But  there  are  many  other  bases  used,  to 
lessen  the  cost  and  for  other  and  legitimate  purposes; 
for  instance,  as  where  the  reds  are  to  be  used  for  dipping. 

Such  heavy-bodied  bases  as  white  lead  or  orange  min- 
eral would  be  entirely  unsuited  for  such  a  purpose.  Their 
heavy  weight  would  soon  precipitate  them  down  to  the 
bottom  of  the  dipping  tanks.  For  this  purpose  the 
lightest-weight  base  that  it  is  possible  to  find  is  the  one 
which  answers  the  purpose  best  of  any,  and  will  remain 
in  suspension  in  the  thinning  liquid  a  much  longer  time 
than  the  heavier  bases  without  settling  down  to  the 
bottom. 

Whatever  the  base  may  be,  or  the  character  of  the 
coloring  agents  used  for  their  dyeing,  the  process  of 
making  the  vermilion  reds  is  a  simple  one.  There  can 
be  but  little  difference  in  the  manner  of  the  handling  of 
the  Various  manufactures.  The  claims  of  superiority, 
etc.,  made  by  some  on  the  strength  of  these,  must  be 
looked  upon  with  suspicion.  The  superiority  rests  alto- 
gether upon  the  quality  of  the  dye,  and  of  course  proper 
regard  to  fixing  it. 

The  base  and  coloring  dye  is  agitated  in  large  vats  and 
allowed  to  settle,  and  after  the  supernatant  liquid  has 
been  withdrawn,  the  pulp  color  is  placed  upon  filtering 
cloth  and  covered  with  the  same.  It  is  then  put  in  the 
filters,  where  the  liquid  is  pressed  as  dry  as  possible.  The 
flat  cakes  are  then  taken  to  the  dry-house  and  dried  out 
bone  hard,  after  which  they  are  pulverized  and  are  ready 
for  market. 


RED  PIGMENTS  103 

Properties  and  Uses 

For  distemper  painting,  the  cheaper  vermilion  reds 
are  of  little  value.  The  coloring  matter  fades  rapidly 
away  when  exposed  to  sunlight,  as  it  is  unprotected 
by  varnish.  The  good  reds  stand  much  better, 
but  they  will  darken  and  become  dingy,  losing  the 
charming  rich  tone  which  they  possess  in  varnish. 
The  cheap  kinds  usually  bleach  white  if  made  on 
a  white  base;  even  those  made  on  an  orange  mineral 
base  will  become  of  a  light  pink,  eventually  changing 
to  white.  It  is  therefore  unadvisable  to  use  such  in 
distemper. 

The  vermilion  reds  which  are  designated  as  permanent 
reds  and  sold  by  manufacturers,  are  usually  so  to  a  good 
degree,  and  are  really  more  so  than  English  vermilion, 
especially  the  crimson-toned  ones  if  they  are  used  under 
varnish,  and  the  varnish  coating  is  renewed  as  it  decays 
away.  This  is  especially  true  of  the  Para  red. 

Coach  and  implement  manufacturers  use  enormous 
quantities  of  those  reds.  Every  country  repair  shop 
keeps  some  in  stock.  Japanning  works  use  them  and 
they  may  be  said  to  have  displaced  the  genuine  vermilion 
or  nearly  so. 

For  striping  purposes  they  have  so  far  been  unable  to 
replace  the  pale  English,  as  they  do  not  possess  the  same 
degree  of  opacity.  In  this  one  instance,  the  genuine  is 
likely  to  hold  its  own. 

Ammoniacal  vapors  are  injurious  to  these  reds,  and  they 
should  never  be  used  where  they  are  likely  to  be  exposed 
to  their  influence.  Nor  should  they  be  used  for  the  mak- 
ing of  tints.  They  are  injuriously  acted  upon  by  most 
pigments  they  come  in  contact  with.  They  should 
be  used  alone,  just  as  they  are. 


104  MODERN  PIGMENTS 

They  are  usually  ground  fine  enough  for  use,  ready 
for  the  thinner  or  vehicle  that  is  to  serve  for  their 
application. 

They  are  also  found  in  the  supply  stores  ground  up  in 
oil  or  in  japan.  Some  manufacturers  do  not  sell  their 
highest  grades  of  Para  reds  in  any  other  form,  claiming 
that  they  fear  a  misuse  of  the  dry  pigment  which 
would  hurt  the  reputation  of  the  goods;  there  may  be 
something  in  this  claim,  but  it  looks  fishy. 

AMERICAN  VERMILION 

Character  and  Uses 

So-called  "  American  "  vermilion  is  not  an  American- 
made  quicksilver  vermilion,  as  the  name  would  indicate. 
It  is  not  even  an  imitation  of  it,  and  for  that  reason  it  is 
not  classed  with  the  vermilion  reds  or  imitation  ver- 
milions, nor  described  under  that  heading. 

It  is  a  dark  chromate  of  lead,  of  a  very  deep  orange  in 
tone.  It  is  crystalline  in  the  form  of  its  atoms,  and 
to  this  is  due  its  brilliancy.  It  should  not  be  ground,  as 
grinding  crushes  its  crystals  and  destroys  its  beauty  in  a 
great  degree. 

Previous  to  the  introduction  of  the  vermilion  reds,  it 
was  much  more  extensively  used  than  it  is  now  by  the 
implement-manufacturing  interests,  but  to-day  on  account 
of  its  duller  color  —  which  may  be  called  a  brown  orange 
red  alongside  of  the  vermilion  reds,  whose  clear  scarlet 
it  lacks  —  it  is  very  seldom  used  by  them,  as  these  have 
entirely  supplanted  it. 

American  vermilion  is  fairly  permanent.  Instead  of 
fading,  it  becomes  a  darker  brown  in  time.  Under  the 
exposure  to  sulphureted-hydrogen  gases  it  turns  black, 
like  most  all  lead  products. 


RED  PIGMENTS  105 

It  is  still  used  by  a  very  few  wagon  and  implement 
manufacturers  in  combination  with  red  lead,  either  as  a 
sort  of  a  trademark  to  distinguish  it  from  others,  or  in 
mixtures  with  vermilion  reds,  as  it  is  thought  by  some 
to  prevent  the  bleaching  out  of  the  cheap  reds. 


CHAPTER  IX 
RED  PIGMENTS  (Continued) 

*  /ry 

VENETIAN  REDS 

History  and  Manufacture 

As  the  name  of  this  pigment  indicates,  at  some  remote 
time  the  Venetians  must  have  introduced  it  to  the  world. 
It  is,  or  rather  was,  a  natural  earth,  and  red  earths  vary- 
ing greatly  in  tone  are  found  in  all  parts  of  the  world.  In 
Europe,  but  especially  in  Italy  and  near  the  city  of 
Venice  to  which  it  owes  its  name,  it  is  plentiful.  Similar 
reds  have  been  in  use  from  times  immemorial  in  the 
decoration  of  many  objects  by  the  ancient  civilizations 
whose  long-hidden  remains  of  art  have  been  brought  to 
light  in  the  recent  past. 

All  these  natural  earths  of  a  red  tone  owe  their  coloring 
matter  to  ferric  oxide,  and  therefore  vary  greatly  in  tone, 
in  the  quality  and  in  the  percentage  of  ferric  oxide  con- 
tained in  them.  This  is  to  be  expected,  and  it  could  not 
be  otherwise.  The  base  or  earth  upon  which  the  ferric 
oxide  has  become  associated  varies  with  each  bed  from 
which  it  is  taken.  Therefore  there  is  not  and  cannot  be 
any  standard  whereby  to  judge  the  value  or  purity  of 
these  reds. 

The  above  does  not  apply  to  what  is  now  known  as 
Venetian  red,  which  is  made  artificially.  These  arti- 
ficial reds  can  be  depended  upon,  not  only  as  to  the 
coloring  and  its  uniformity,  but  also  in  the  quantity 

100 


RED  PIGMENTS  107 

contained  in  a  given  weight.  The  late  William  C.  Wilson, 
whose  name  has  been  mentioned  elsewhere,  describes  its 
manufacture  minutely  in  an  essay  published  in  Painting 
and  Decorating  a  few  years  ago.  The  essay  is  too  long 
for  reproduction  in  full  for  the  purposes  of  this  treatise, 
but  the  main  features  of  it  are  contained  in  the  following 
description:  "Venetian  red,  like  ocher,  owes  its  coloring  to 
oxide  of  iron-.  Oxide  of  iron  does  more  for  color  than  any 
mineral.  "Venetian  red  is  made  in  various  ways.  If 
copperas  be  placed  in  retorts  and  subjected  to  a  high 
temperature,  fuming  sulphuric  acid  will  distill  over  and 
a  red  material  will  remain.  This  red  residue  when  reduced 
to  a  fine  powder  by  powdering  and  levigation,  becomes 
colcothar,  crocus  or  rouge,  and  is  a  pure  oxide  of  iron.  It 
is  mixed  with  gypsum  in  varying  proportions  as  desired, 
or  up  to  a  fixed  standard  established  for  certain  brands. 
The  so-called  English  Venetian  reds  are  of  this  character. 
The  standard  adopted  for  a  first-class  article  of  Venetian 
red  is  about  five  parts  of  gypsum  to  one  part  of  the  crocus. 
Gypsum  is  sulphate  of  lime,  and  experience  has  proven 
that  it  is  one  of  the  best  bases  for  colors,  and  that  Venetian 
reds  made  from  it  and  crocus  are  good  paints.  The 
Venetian  reds  are  coarse  and  require  considerable  labor 
to  bring  them  to  perfection.  On  this  account,  it  has  been 
customary  to  consider  Venetian  red  when  ground  in  oil 
as  a  coarsely  ground  color.  Finer  grades  of  red  are  pre- 
pared that  are  not  only  finely  ground,  but  are  made  with 
a  smaller  percentage  of  gypsum,  and  then  they  are  known 
as  super  Venetian  reds  or  Turkey  reds. 

"Gypsum  is  not  alone  used  as  a  base  for  the  crocus; 
barytes  and  whiting  are  frequently  used  for  the  purpose. 
The  great  weight  of  barytes  and  its  little  power  to  absorb 
and  combine  with  oil  renders  it  a  very  undesirable  base, 
the  red  so  made  having  none  of  the  durability  of  the 


108  MODERN  PIGMENTS 

gypsum  red.  To  the  paint  grinder,  it  saves  a  large  per- 
centage of  linseed  oil  in  grinding,  and  that  is  the  costliest 
part  of  it. 

"A  gypsum  red  requires  from  25  to  30  pounds  of  oil  to 
every  hundredweight  of  the  color  to  grind  it  —  a  barytes 
red  requires  only  12  to  15  pounds  for  the  same  quantity. 

"But  this  is  not  all  the  saving  to  the  grinder,  for  the 
mills  will  grind  nearly  twice  as  much  of  the  barytes  reds 
as  they  will  of  the  gypsum  reds  in  the  same  number  of 
hours,  and  the  former  will  look  smoother  than  the  last, 
and  require  smaller  packages  to  hold  it  in. 

"Whiting  makes  a  better  base  than  barytes,  but  it  is 
still  inferior  to  gypsum,  its  chief  attraction  to  the 
grinder  being  the  smooth-looking  paint  it  makes. 

"All  reds  made  by  copperas  are  deep  in  tone.  Certain 
ocherous  earths  are  found  which  on  "furnacing"  or  cal- 
cinating will  give  bright  reds,  and  some  of  these  give  very 
light  shades." 

The  terms  American  Venetian  reds  and  English  Vene- 
tian reds  mean  very  little  to-day  other  than  as  designa- 
tions for  the  low  and  high  qualities  of  that  pigment. 
The  better  or  higher  qualities  are  sold  under  the  name 
of  "English"  Venetian  red,  and  the  poorer  qualities  under 
the  name  of  "American." 

As  good  qualities  of  Venetian  reds  are  made  in  America 
to-day  as  any  that  are  produced  in  England,  and  impor- 
tations of  this  pigment  from  that  country  are  very  much 
reduced.  The  good  grades  of  the  reds  made  in  the  United 
States  are  branded  and  sold  as  English  Venetian  reds. 
The  name  signifies  quality  only,  and  ours  of  the  same 
excellence  are  as  much  entitled  to  it  as  the  imported. 

Large  manufacturing  plants  exist  and  have  been  in 
operation  for  years  in  Philadelphia,  Pa.,  Worcester, 
Mass.,  and  on  a  smaller  scale  in  other  localities. 


RED  PIGMENTS  109 

The  so-called  American  Venetian  reds  are  principally 
barytes  and  crocus  mixtures,  or  a  calcined  ocher  of  poor 
quality  and  but  one  degree  removed  from  a  Spanish 
brown,  much  of  which  is  prepared  arid  marketed  from 
Baltimore,  St.  Louis,  etc. 

Many  more  pages  could  be  added  to  the  above  in 
describing  the  processes  used  in  the  manufacture  of  the 
higher  grades  of  Venetian  reds,  but  they  are  too  intricate 
and  lengthy  to  be  of  interest  to  the  general  reader,  and 
would  be  of  value  only  to  the  color  maker. 

Properties  and   Uses 

It  is  enough  to  say  that  Venetian  reds  made  upon  a 
gypsum  base  will  prove  much  more  satisfactory  for  the 
painter's  purposes  than  the  others.  Gypsum  seems  to 
have  the  property  of  holding  up  the  color  and  keeping 
it  from  fading,  or  rather  of  keeping  it  from  darkening,  as 
is  natural  for  the  crocus  or  oxide  of  iron. 

It  has  been  seen  that  Venetian  red  is  an  artificial  color, 
and  that  therefore  it  must  contain,  and  in  fact  does  con- 
tain, varying  quantities  of  ferric  oxide.  So  one  must  be 
prepared  to  allow  considerable  latitude  for  variations  in 
this  regard.  A  good  sample  should  not  contain  less  than 
20  per  cent  in  its  composition.  Again,  the  mere  reading 
of  an  analysis  would  throw  but  little  light  on  quality,  as 
some  of  the  poorest  of  the  natural  calcined  earths  which 
are  sold  as  American  Venetian  would  show  up  a  very 
much  higher  percentage  of  it  than  the  best  of  the  gypsum- 
base  made  ones  usually  do.  Some  of  these  cheap  cal- 
cined earth  reds  show  from  25  to  65  per  cent  of  ferric 
oxide  in  their  composition  —  such  as  it  is.  Most  of 
these  are  only  fit  for  the  mortar  heap  as  colors,  and  the 
difference  in  cost  is  so  slight  that  they  should  never  be 
used  as  pigments  for  painting  when  the  better  qualities 


110  MODERN  PIGMENTS 

can  be  had  —  even  if  it  were  at  a  much  greater  difference 
in  cost  than  that  which  really  exists. 

Venetian  reds  made  upon  a  gypsum  base  are  reliable, 
and  practically  unchangeable  by  exposure  to  light  and 
air.  They  darken  a  trifle,  but  that  is  caused  chiefly  by 
the  darkening  of  the  linseed  oil  by  age.  There  is  a  cause 
for  this  belonging  to  the  pigment  itself,  and  that  is  the 
absorption  of  a  small  percentage  of  hydrogen  from  the 
atmosphere,  and  of  a  partial  hydration  of  the  oxide  con- 
verting it  into  hydrate-ferric  oxide.  This  is  very  slight 
and  hardly  worth  reckoning  in  the  gypsum-based  reds. 

Venetian  red,  either  the  natural  or  the  artificial,  may 
be  mixed  with  other  pigments  with  perfect  safety,  and 
it  is  invaluable  for  mixing  with  white  lead  for  the  com- 
pounding of  many  tints. 

It  can  be  used  for  any  kind  of  painting  in  oil  or  dis- 
temper. The  better  grades  contain  an  excellent  body 
or  opacity,  and  usually  will  cover  solidly  over  any  other 
color  on  which  they  may  be  applied  in  one  coat. 

It  is  used  as  a  ground  coat  somewhat  lightened  up  with 
white  pigment,  for  the  more  expensive  reds  in  coach  or 
carriage  work,  for  the  reds  used  in  painting  agricultural 
implements  and  machinery  of  all  kinds.  It  is  one  of  the 
few  colors  that  cannot  be  spared,  and  if  lost  (which  it 
is  not  likely  to  be)  could  be  replaced  by  no  other  red 
pigments. 

INDIAN   REDS 

Production  and  Preparation  for  Use 

This  most  excellent  pigment  has  been  known  from  the 
earliest  ages  under  various  names,  usually  derived  from 
the  countries  from  which  it  was  formerly  produced,  as 
Indian  red  from  India,  Persian  red  from  Persia,  and  so 
on.  By  far  the  greatest  quantity  of  it  that  found  its 


RED  PIGMENTS  111 

way  into  England,  and  from  thence  was  exported  to 
America,  was  shipped  from  Bengal.  Hence  its  name  of 
Indian  red,  by  which  it  is  best  known  in  both  countries. 

It  is  a  very  rich  hematite  iron  ore.  Its  coloring  matter  is 
peroxide  of  iron.  It  is  an  anomalous  red  of  a -purple-russet 
hue,  and  highly  valued  when  of  good  quality  for  its  lakey 
tones  in  making  tints  by  compounding  with  a  white  base. 

It  is  a  coarse  powder  in  its  native  state;  full  of  hard 
and  extremely  brittle  particles  of  dark  appearance  and 
sometimes  magnetic.  It  is  greatly  improved  by  grinding 
and  washing.  Its  chemical  composition  is  such  that  it 
has  a  tendency  to  deepen.  It  is  most  permanent;  neither 
light  nor  impure  air,  mixing  it  with  other  pigments,  time 
nor  fire,  seem  to  cause  it  to  change  in  any  way. 

Being  very  opaque,  it  covers  remarkably  well.  The 
tones  of  Indian  reds  vary  greatly  in  their  hues;  that 
which  is  rosy  being  considered  the  best,  as  affording  the 
purest-toned  tints. 

As  long  as  Indian  reds  were  imported  and  consisted  of 
iron  ores,  and  until  such  recent  times  as  the  eighties,  there 
was  and  could  be  no  recognized  standard  of  purity  for  it. 
Containing  great  strength  of  coloring  matter,  it  was  the 
usual  thing  to  adulterate  it  with  from  50  to  75  per  cent  of 
makeweight  foreign  matter,  and  still  it  remained  strong 
enough  to  disarm  the  suspicions  of  the  painters  of  that 
period.  Now,  however,  it  is  different.  No  Indian  red 
can  be  recognized  as  pure  that  does  not  show  upon  analy- 
sis at  least  95  per  cent  of  peroxide  of  iron,  and  frequently 
some  are  found  to  analyze  97  and  98  per  cent  pure.  The 
reason  for  this  great  purity  is  that  to-day  most  of  it  is 
made  artificially,  as  pigments  having  iron  as  a  coloring 
agent  are  nearly  all  so  made.  It  is  thus  possible  to  main- 
tain a  specific  standard  of  purity  in  the  processes  of  their 
manufacture. 


112  MODERN  PIGMENTS 

It  is  made  in  a  similar  manner  to  that  related  of  the 
manufacture  of  crocus  used  in  the  production  of  Venetian 
red,  with  this  difference,  that  instead  of  sulphate  of  iron 
being  the  source  of  supply,  iron  pyrites  replaces  it. 
The  processes  vary  to  some  extent  from  that  also  ; 
these  are  too  complicated  for  description  here,  but  may 
be  inferred.  The  sulphuric  acid  is  driven  from  the  pyrites, 
and  the  residue  forms  the  base  of  the  Indian  red. 

Properties  and  Uses 

A  peculiarity  belonging  to  all  iron  pigments,  and  also 
common  to  Venetian  red,  is  that  the  lighter  the  tone,  the 
stronger  it  will  prove  in  coloring  matter;  thus  the  darkest 
shades  of  them  are  the  weakest  in  this  respect.  Hence 
the  rosiest  of  the  Indian  reds  are  the  strongest. 

Indian  reds  are  selected  and  graded  according  to  their 
shade,  and  it  is  usual  for  color  grinders  to  put  them  up  in 
three  different  shades — the  pale,  or  rose  toned ;  the  medium 
or  the  one  between  that  and  the  dark  which  makes  the 
violet  shades.  The  pale  produces  the  rosy  tints,  and  the 
dark  the  lilac-toned  ones.  Indian  reds  are  chiefly  useful 
for  the  making  of  a  wide  range  of  beautiful  tints  associated 
with  a  white  base.  It  is  also  used  as  a  self  color,  but  in  a 
very  limited  way. 

It  is  employed  by  all  classes  of  painters,  decorators, 
and  artists  for  painting  in  oil,  in  japan,  or  in  distemper, 
and  with  universal  satisfaction. 

TUSCAN  RED 

Manufacture 

Tuscan  red  is  a  compound  color;  properly  it  is  an 
enriched  Indian  red.  All  that  has  been  said  of  Indian  red, 
applies  to  it  in  a  great  degree,  as  that  pigment  is  the 


RED  PIGMENTS  113 

base.  The  enrichment  is  due  to  the  use  of  a  lake  to  dye 
the  Indian-red  base  and  give  it  the  beautifully  subdued 
crimson  tones. 

As  usually  the  Indian  red  is  entirely  too  strong,  its 
strength  is  reduced  by  combining  it  with  barytes,  whiting, 
or  gypsum.  The  combining  is  done  in  a  tank  by  the 
addition  of  water  with  trituration.  While  still  in  a 
diluted  state,  the  lakes  are  added  to  the  mixture.  The 
color  is  allowed  to  deposit,  when  the  supernatant  water  is 
withdrawn,  the  pulp  color  pressed  out,  dried  and  pul- 
verized, packaged,  and  sold  as  Tuscan  red. 

Properties  and  Uses 

It  stands  to  reason  that  the  better  the  lake  used  in 
dyeing  the  Tuscan  red,  the  better  that  will  be  in  quality. 
If  the  red  has  been  colored  up  with  the  cheaper  and 
inferior  aniline  dyes, — as  in  making  the  qualities  of  Tuscan, 
—  it  will  fade  away  upon  little  provocation,  and  prove  as 
fleeting  as  rose  pink  and  as  prompt  in  disappearance. 

Again,  in  the  best  grades  of  Tuscan  reds  the  enriching 
lake  is  practically  permanent,  or  the  manufacturers  could 
never  guarantee  them  to  stand  350°  F.  of  heat  before 
any  sign  of  changes  taking  place  in  any  way.  Tuscan  reds 
made  thus  are  therefore  very  permanent,  and  are  ex- 
tensively used  for  the  painting  of  passenger  cars,  one 
of  the  most  rigorous  tests  for  any  color;  they  are  also  used 
with  good  results  in  the  painting  of  steam  pipes,  radiators, 
etc.,  another  very  hard  test  of  the  permanency  of  a  color; 
probably  Tuscan  red  is  more  extensively  used  for  such 
painting  than  any  other  color.  The  quality  test  is  the 
all-important  one  for  this  pigment.  The  test  for  mere 
strength  of  the  amount  of  coloring  matter  contained 
amounts  to  nothing,  Tuscan  reds  being  never  used  for 
the  making  of  tints.  In  this  regard  they  are  very  inferior 


114  MODERN  PIGMENTS 

to  the  Indian  reds.  They  are  used  exclusively  for  solid 
self-painting,  and  for  this  purpose  are  very  much  better 
adapted  than  are  the  Indian  reds,  because  they  possess 
far  richer  tones. 

It  is  really  difficult  to  test  Tuscan  reds.  The  staying 
quality  of  tone  is  what  counts  with  them,  and  that  is  not 
easily  determined  on  the  spot  —  time  only  can  do  that. 
Some  of  the  very  poorest  ones  will  show  up  bright  and  rich 
when  first  taken  out  of  a  can.  This  is  where  confidence 
in  the  name  of  the  manufacturers  will  have  to  decide 
which  of  two  samples  one  shall  buy.  If  they  have  an 
established  reputation  made  for  their  Tuscan  red,  let  that 
guide.  When  so  found,  better  be  slow  in  changing  to 
another  that  is  unknown. 

It  is  used  by  many  manufacturers  of  machinery  and 
implements,  and  when  it  is  properly  striped  with  a  light 
orange  it  presents  a  fine  effect.  The  machinery  looks 
rich  but  not  gaudy,  and  it  is  a  relief  from  the  overdone 
scarlet  that  it  is  customary  to  use  for  such  painting. 

RED   OXIDE  OF  IRON 

Properties  and  Uses 

Within  the  past  twenty-five  years,  the  red  oxide  of  iron 
has  been  so  listed  by  many  color  grinders.  It  is  a  power- 
ful red  and  to  be  had  in  many  shades.  The  scarlet  shade 
is  the  most  preferred.  These  scarlet  oxides  are  the 
brightest  and  strongest  known.  They  should  be  pure, 
and  this  the  scale  test  will  reveal  at  once.  When  used 
in  oil,  it  should  be  thinned  to  the  last  degree,  as  it  is  so 
strong  that  the  color  will  not  show  at  best  advantage 
unless  it  is  so  thinned. 

It  is  chiefly  valuable  for  the  making  of  tints  with  white 
bases  where  the  least  quantity  of  color  is  wanted  to  pro- 


RED  PIGMENTS  115 

duce  the  desired  effect.  It  is  so  very  strong  that  one 
pound  of  it  will  turn  a  ton  of  white  lead  to  a  decided 
flesh  tint.  In  other  respects,  it  is  of  the  same  character 
of  red  as  the  Venetian  red,  and  it  is  questionable  if  it  will 
ever  be  able  to  take  the  place  of  that  red  even  for  the 
making  of  tints,  because  the  base  (gypsum)  in  a  good 
Venetian  red  acts  as  a  preservative  to  the  white  lead,  and 
in  a  small  measure  helps  to  retard  chalking.  This  is 
also  partly  due  to  the  greater  quantity  of  linseed  oil  which 
a  tint  so  prepared  will  contain. 

Scarlet  oxide  of  iron,  notwithstanding  that  it  is  abso- 
lutely pure,  has  never  become  popular  among  the  painters. 
It  is  now  nearly  twenty-five  years  since  it  was  first  offered 
for  sale  in  a  regular  way,  but  its  growth  into  favor  is  so 
slow  that  some  grinders  who  listed  it  a  few  years  ago 
have  abandoned  it.  At  best  it  is  a  curiosity.  Should 
it  ever  grow  into  favor,  it  would  soon  be  placed  on  sale 
again,  as  it  is  as  easily  procurable  as  the  crocus  of  the 
Venetian  red.  The  trouble  is  that  it  does  not  fill  a 
"  long-felt  want,"  and  that  it  is  only  a  stronger  edition  of 
Venetian  red,  and  that  is  of  questionable  value. 


CHAPTER   X 

RED  PIGMENTS  (Continued) 

RED  LEAD 

History  and  Chemistry 

THIS  pigment  was  known  to  the  ancients,  and  is  of  great 
antiquity.  It  was  known  and  used  in  the  enameling  of 
pottery,  brick,  and  terra-cotta  by  the  Greeks  and  Romans, 
and  was  used  also  by  them  in  their  decorative  paintings. 
It  was  formerly  known  under  the  name  of  minium,  and  is 
still  known  under  that  name  in  many  parts  of  the  world. 
It  is  the  product  of  the  oxidation  of  massicot,  but  it  is 
also  obtained  by  the  calcination  and  oxidation  of  white 
lead.  It  is  a  double  oxide  of  lead,  massicot  or  litharge 
being  the  monoxide  of  it.  Its  chemical  formula  is  Pb4O5. 

Properties  and  Uses 

Red  lead  has  the  property  of  saponifying  linseed  oil  to 
the  extent  of  about  one  third  of  the  quantity  necessary  to 
thin  it  for  application  with  the  brush.  It  is  a  very  good 
and  strong  drier  of  linseed  oil,  and  for  that  reason,  joined 
to  that  of  the  saponification  of  it,  it  cannot  be  ground  to  a 
paste  form  with  linseed  oil  as  most  other  pigments  can 
be,  as  it  will  solidify  into  a  hard  mass  in  a  short  time. 
Owing  to  this  peculiarity,  which  is  a  common  property  of 
all  the  other  oxides  of  lead,  it  is  usual  to  buy  it  in  a  dry, 
powdered  state. 

Red  lead  is  a  most  excellent  paint  for  use  over  iron  as  a 
primer  next  to  the  bare  metal.  It  is  also  a  most  excellent 

116 


RED  PIGMENTS  117 

primer  for  other  metals,  and  it  is  becoming  more  important 
every  year  now  that  so  much  structural  iron  and  steel  are 
being  used  in  the  construction  of  buildings  in  all  our 
large  cities.  Engineers  and  architects  are  unanimous  in 
recommending  it  as  a  first  or  priming  coat  over  iron,  and 
many  specify  it  to  be  applied  at  the  rolling  mills.  It  is 
the  best  primer  that  can  be  used  for  such  a  purpose. 

Formerly  it  was  extensively  used  in  wagon  painting  for 
the  running  gears,  and  some  factories  still  use  it  in  that 
way.  It  seems  to  adhere  with  such  tenacity  on  the  wheels 
that  it  is  not  easily  scratched  or  marred.  The  felloes  of 
wheels  painted  with  other  materials  soon  show. 

Like  all  lead  pigments  it  is  easily  affected  by  sulphur- 
eted-hydrogen  gases,  and  it  will  turn  black  when  exposed 
to  them.  When  exposed  to  the  direct  action  of  the  sun's 
rays  it  has  a  tendency  to  bleach.  This  is  no  doubt  due 
to  the  loss  of  some  of  its  oxygen  and  to  a  return  towards 
a  monoxide  state,  the  normal  condition  of  the  lead  oxides. 

As  to  its  wearing  qualities,  there  is  nothing  in  the  line 
of  pigments  that  equals  it.  It  becomes  nearly  as  hard  as 
a  coat  of  metallic  lead  itself  —  some  say  harder.  As  has 
been  said,  a  wagon's  running  gear  painted  with  it  will 
stand  knocks,  friction,  and  anything  in  reason  without  the 
paint  coming  off,  while  any  other  red  would  come  off  to  the 
bare  wood. 

At  the  several  navy  yards  of  the  United  States,  but 
especially  at  Norfolk,  Va.,  the  authorities  have  come  to  the 
conclusion  that  there  is  nothing  to  equal  it  for  the  priming 
of  iron,  and  they  specify  its  use  for  that  purpose  in  ship 
construction.  Again,  when  at  the  end  of  a  cruise  ships 
come  in  for  a  general  overhauling  in  the  dry  docks,  and 
after  the  old  paint  has  been  burned  off,  they  are  invariably 
treated  to  a  coat  of  red  lead  as  a  foundation  for  whatever 
may  be  wanted  to  go  on  top  of  that. 


118  MODERN  PIGMENTS 

On  account  of  its  heavy  weight,  it  is  never  used  in  dis- 
temper; and  from  its  tendency  to  blacken  under  the  action 
of  sulphurous  fumes  and  to  lighten  under  strong  sunlight, 
it  is  never  used  for  that  kind  of  work. 

Its  chief  and  best  use  is  when  associated  with  linseed 
oil  for  the  purposes  already  indicated. 

Many  of  the  white  lead  corroders  also  make  red  lead. 
This  they  put  up  in  wooden  kegs  of  same  weights  as  those 
of  white  lead,  viz.,  12J's,  25's,  50's,  100's,  200's,  and  250's 
being  the  usual  quantities.  It  is  usually  pure  when  the 
label  says  "Strictly  Pure/'  and  is  accompanied  by  the 
name  of  the  corroding  firm.  There  is  some  difference  in 
the  qualities  of  it,  some  being  more  crystalline  than  others, 
and  therefore  richer  in  tone.  It  therefore  requires  some 
little  knowledge  of  brands  to  be  able  to  buy  the  best 
without  seeing  them  first.  For  the  priming  of  structural 
iron,  this  does  not  make  any  material  difference;  but  if 
the  lead  is  to  be  the  finishing  coat,  as  in  wagon-gear  paint- 
ing, then  that  is  another  story. 

The  above  ends  the  list  of  useful  red  pigments 
employed  in  general  painting;  the  remainder  are  mainly 
compound  pigments  and  the  lakes,  which  are  seldom 
handled  in  general  painting  excepting  in  tinting  or  color- 
ing walls  and  for  decorative  purposes.  The  car  and 
carriage  painters,  however,  use  some  of  these  extensively. 
The  japanning  works  also  use  them,  and  some  are  used 
for  enameling  pottery  and  colored  brick. 

LAKES. 

General  Remarks   Concerning   Them 

Under  the  generic  name  of  lakes,  a  class  of  pigments 
is  placed  upon  the  market  which  differs  in  one  respect 
from  all  the  others.  As  a  rule  they  are  transparent,  and 


RED  PIGMENTS  119 

are  never  used  alone  as  a  covering  coat  in  oil  painting. 
When  used  in  oil  or  varnish,  it  is  over  some  other  coat 
of  color  which  sometimes  is  similar  in  tone  to  that  of 
their  own,  but  which  has  made  a  solid  covering,  and  they 
are  used  in  that  case  for  enriching  it.  Or  if  placed  over 
a  color  which  is  dissimilar  in  tone  to  their  own  —  one 
that  will  show  through  their  own  coating,  which  permits 
certain  effects  to  be  thus  produced  which  would  not  have 
been  possible  otherwise.  This  is  called  glazing,  in  the 
parlance  of  the  craft.  That  is  their  chief  use  in  oil  or 
varnish.  Some  also  make  beautiful  tints  with  white  lead 
or  zinc  white  bases,  especially  the  latter,  and  that  with 
any  of  the  vehicles. 

Lakes  are  extensively  used  by  the  wall-paper  manu- 
facturers, and  in  distemper  by  all  classes  of  decorators 
and  artists.  The  car  and  carriage  trades  also  use  them 
largely,  and  artists  would  hardly  know  how  to  get  along 
without  them. 

Lakes  are  invariably  made  by  the  use  of  a  dyeing 
agent  upon  a  base  that  it  is  calculated  will  best  hold  it. 
For  this  purpose,  many  substances  and  combinations  of 
them  are  used.  Alum  is  commonly  the  principal  one, 
but  gypsum,  whiting,  and  barytes  are  also  employed  for 
the  purpose. 

RED  LAKES 

Among  the  reds  are  to  be  found  some  of  the  most  valu- 
able and  permanent  of  the  lakes.  This  permanency  was 
originally  due  to  the  use  made  of  coloring  matter 
extracted  from  the  madder  plant.  This  is  now  obsolete, 
as  the  same  coloring  substance  which  was  at  one 
time  extracted  from  the  madder  root  is  now  much 
more  economically  extracted  from  coal  tar  as  alizarin 
and  purpurin. 


120  MODERN  PIGMENTS 

ALIZARIN  AND  PURPURIN 

Extraction  and  Preparation 

Church  says:  "Both  of  these  coloring  substances  are 
now  made  from  anthracene.  This  compound  occurs  in 
coal  tar  in  a  crystalline  fluorescent  hydrocarbon  C14H10. 
By  a  series  of  processes  this  substance  gives  rise  to 
alizarin  and  purpurin,  which  are  in  all  respects  identical 
with  those  coloring  matters  derived  from  the  madder 
plant  itself.  The  artificial  alizarin  of  commerce  contains 
several  other  coloring  matters,  two  of  which  are  better 
known  than  the  others:  these  are  anthrapurp^irin 
(C14H5O8)  and  purpuroxanthin  (C14HgO4).  Purpurox- 
anthin  is  also  present  in  the  natural  pigments  derived 
from  madder  root,  but  it  exists  in  smaller  proportions. 
Of  all  these  compounds  alizarin  is  the  most  important 
and  best  known,  and  yields  lakes  having  various  hues  of 
crimson,  rose,  purple,  violet,  and  maroon  according  to  its 
purity,  its  concentration,  and  the  nature  of  its  base 
(alumina,  iron  oxide,  or  lime  with  alumina)  with  which 
it  is  associated.  The  purpurin  and  anthrapurpurin 
resemble  each  other  closely,  and  give  pigments 
which  are  generally  characterized  by  more  orange  and 
red  hues  than  are  those  obtained  by  alizarin.  The 
rose  and  pink  madders  and  madder  carmines  of  com- 
merce are  generally  so  manufactured  as  to  include  for 
their  coloring  constituents  much  alizarin  and  very 
little  purpurin." 

The  process  of  extracting  alizarin  and  purpurin  from 
madder  root  or  from  anthracene  is  far  too  lengthy  and 
complex  for  this  treatise.  It  suffices  to  know  that  it  is 
now  possible  to  obtain,  at  a  comparatively  low  cost, 
excellent  pigments  which  twenty-five  years  ago  would 
have  been  very  expensive. 


RED  PIGMENTS  121 

Manufacture  of  Lakes 

The  preparation  and  manufacture  of  lakes  from 
eosine,  anilines,  alizarin  or  purpurin,  present  no  difficul- 
ties. Of  course,  one  must  be  provided  with  the  proper 
manipulating  devices. 

Madder  lakes  can  be  readily  prepared  from  alizarin 
and  purpurin,  by  dissolving  those  substances  in  the 
smallest  necessary  quantity  of  alkali,  such  as  ammonia 
or  sodium  carbonate,  or  some  pure,  freshly  precipitated 
and  thoroughly  washed  aluminum  hydrate.  While  the 
above  directions  are  simple,  there  is  more  to  that  simple 
process  than  appears  upon  the  surface.  There  are  many 
little  tricks  of  the  trade  that  are  secrets,  and  which  are 
used  in  the  precipitation  of  lakes,  which  enable  one  color- 
maker  to  produce  from  the  very  same  substances  a  lake 
that  looks  brighter  or  which  is  more  permanent  than 
that  made  by  another  manufacturer. 

Fixing  the  coloring  matter  is  an  important  item  in  the 
manufacture  of  lakes.  As  an  illustration  of  how  trifles 
affect  coloring  matter  and  its  durability,  an  incident, 
the  truth  of  which  can  be  vouched  for,  is  given  as  follows : 
The  world-wide  known  and  justly  celebrated  govern- 
ment institution  in  France  —  the  "Gobelins"  —  where 
the  famous  historical  tapestries  are  manufactured,  pre- 
pares all  the  dyes  used  in  the  coloring  of  the  wool.  In 
earlier  days  there  were  no  underground  sewers  in  that  part 
of  the  city  of  Paris,  and  surface  streams  were  depended 
upon  for  the  carrying  away  of  all  sorts  of  liquids.  It 
happened  that  a  small  brook  formed  the  middle  of  the 
street  in  front  of  the  factory,  and  that  the  water  used  for 
the  preparation  of  the  dyes  was  taken  from  it.  The 
water  was  very  impure  and  fetid,  as  it  was  contaminated 
with  animal  matter  from  an  abattoir  (slaughter  house) 


122  MODERN  PIGMENTS 

above  it.  In  the  course  of  the  city's  improvement,  the 
stream  was  diverted  and  made  to  flow  into  underground 
sewers,  so  that  the  Gobelin  factory  was  forced  to  use  city 
water  in  compounding  its  dye  stuffs,  but  some  of  the  most 
admired  shades  could  not  be  reproduced.  It  puzzled  the 
heads  of  the  institution  for  many  years,  searching  for  the 
cause  of  their  inability  to  reproduce  the  beautiful  color- 
ings made  in  former  years.  At  last  they  hit  upon  the 
cause,  and,  as  nearly  as  possible,  they  artificially  con- 
taminated the  pure  water  furnished  by  the  city  to  resemble 
that  which  they  had  once  used,  and  thereupon  they  were 
able  to  reproduce  the  shades  as  of  old.  These  were  due 
to  the  impurities  contained  in  the  water.  This  illustrates 
why  it  is  that  some  manufacturers  are  able  to  and  do  put 
out  brighter  and  better  goods  than  another  can.  This  is 
due  in  many  instances  to  the  water,  or  rather  to  the 
composition  of  the  water  used. 

ROSE  PINK 

Properties  and  Uses 

Rose  pink  is  a  very  cheap  lake  of  purplish-red  tone,  and 
about  the  poorest  one  in  the  whole  range  of  red  lakes. 
Its  coloring  matter  is  evanescent.  It  should  never  be 
employed  for  lasting  work. 

It  is  used  for  coloring  fillers  in  furniture  factories,  also 
by  some  for  staining  cheap  furniture  and  chairs.  It 
looks  rich,  and  usually  remains  so  long  enough  to  enable 
the  furniture  manufacturers  to  dispose  of  the  goods  before 
it  disappears. 

The  best  of  it  is  usually  made  from  Brazil  wood ;  some 
of  the  cheapest  of  the  cheap  aniline  dyes  seem  to  have 
gone  in  the  makeup  of  many  samples  of  it.  As  there  is 
danger  to  those  who  use  this  pigment  —  they  may  be 


RED  PIGMENTS  123 

using  some  of  the  aniline-made  ones  —  unless  one  is  sure 
of  the  brand  being  a  good  one,  it  will  be  best  to  let  it 
alone  and  take  no  chances.  Much  better  lakes  can  be 
had  which  produce  the  same  effects,  but  they  cost  more. 

ROSE  LAKE 

Properties  and  Uses 

This  lake  is  just  one  notch  better  than  rose  pink.  It 
belongs  to  the  same  order  and  tone  of  red,  but,  as  usually 
made,  is  just  a  trifle  lighter  toned  and  more  rosy.  It,  too, 
is  made  from  Brazil  wood  when  it  is  not  made  from 
something  else  (aniline). 

Like  rose  pink  it  fades  away  quickly  upon  exposure 
to  strong  light,  and  but  for  the  fact  that  one  is  charged 
a  little  more  money  for  it  than  for  the  other,  it  would  be 
hard  to  tell  which  is  the  poorer  of  the  two.  In  reality 
it  is  simply  a  lighter  shade  of  rose  pink,  of  a  more  rosy 
tone,  or  not  quite  so  purplish. 

The  same  caution  given  under  the  heading  of  rose 
pink  —  not  to  make  an  indiscriminate  use  of  it  —  will 
apply  with  full  force  to  rose  lake.  This  is  also 
employed  for  the  same  purposes. 

MADDER  LAKES 

Properties  and  Uses 

Under  this  name  will  be  found  all  the  red  lakes  found  in 
commerce  that  are  of  any  good  at  all.  Accordingly,  all  will 
be  listed  under  the  same  heading,  —  all  such  at  least  that 
are  made  by  the  agency  of  alizarin  and  purpurin.  These 
lakes  have  quite  a  wide  range  of  tone,  and  cover  the  whole 
field  of  maroons,  violets,  and  the  pinks,  including  the 
carmine  shades. 


124  MODERN  PIGMENTS 

It  is  useless  to  examine  them  separately,  as  all  have  the 
same  general  characteristics,  the  difference  being  simply 
one  of  tone.  Each  of  them  will,  of  course,  make  a  line 
of  tints  appertaining  to  its  coloring. 

All  color  manufacturers  usually  put  out  several  lakes 
under  fancy  and  proprietary  or  copyrighted  names. 
Coach  color  catalogues  and  price  lists  are  frequently  a 
puzzle  to  the  uninitiated  because  of  some  dozens  of  red 
lakes  of  whose  existence  but  few  may  be  aware.  Many 
are  never  mentioned  by  the  other  competing  firms,  who 
have  a  puzzling  list  of  their  own.  Dry  color  lists  are  also 
swelled  up  and  loaded  down  with  terms  to  the  confusion 
of  the  average  reader.  Each  manufacturer  adopts  a 
name  of  his  own  for  something  that  is  identically  the 
same  as  that  chosen  by  other  competitors,  each  of  whom 
calls  it  by  a  different  name.  This  practice  is  highly  confu- 
sing to  persons  who  are  not  familiar  with  the  trade  custom 
nor  with  the  exact  character  of  the  goods  themselves. 
Therefore,  if  a  person  has  been  buying  a  red  lake  under  the 
glowing  name  of  "Morning  Star,"  and  he  finds  one  that 
matches  it  but  offered  for  sale  under  the  name  of  "  Setting 
Sun,"  he  need  not  worry  if  he  is  forced  to  use  the  latter. 
In  all  likelihood  they  are  identical,  and  he  will  not  be 
disappointed  in  their  use.  The  main  point  is  to  insist 
upon  getting  an  alizarin  or  purpurin  red,  and  the  dealer's 
guarantee  that  such  a  lake  is  thus  made  is  the  main  thing. 
Dealers  who  handle  lakes  should  be  able  to  answer  such 
questions;  and,  if  they  were  questioned  a  few -times,  would 
be  forced  to  post  themselves  if  they  do  not  already 
know  —  and  the  y  should  know  —  what  sort  of  material 
they  handle  and  offer  for  sale. 

The  madder  reds  and  madder  lakes  are,  all  of  them, 
what  may  be  called  permanent  under  proper  conditions, 
and  can  be  called  so  by  contrast  and  in  comparison  with 


RED  PIGMENTS  125 

those  made  from  cochineal,  Brazil  wood,  etc.  They  are 
very  satisfactory  in  use.  The  range  of  color,  covering 
as  it  does  every  shade  of  red,  purple,  and  maroon,  is 
sufficiently  varied  for  the  wants  of  any  one.  As  they 
enter  into  the  composition  of  the  better  class  of  vermilion 
reds,  these  might  also  be  classed  with  them;  thus  the  field 
of  reds  would  include  the  scarlet  tones.  However,  those 
reds  are  solid  opaque  covering  goods,  in  nowise  trans- 
parent, and  they  cannot  be  included  with  the  lakes. 

There  are  a  number  of  reds  made  in  a  manner  similar 
to  the  lakes,  but  upon  an  opaque  base.  These  are  used 
for  solid  painting  on  that  account,  and  for  that  reason 
these  reds  cannot  be  classed  with  lakes. 

The  crimson  solid-covering  reds  are  chiefly  used  by 
the  carriage  trade,  and  are  known  under  various  names, 
unfortunately  all  proprietary,  thereby  causing  more  con- 
fusion. Of  this  description  are  the  many  road-cart  reds, 
so  called.  The  cheaper  kinds  of  those  reds  are  made 
from  cheap  aniline  dyes,  and  are  therefore  fugitive;  the 
better  are  from  alizarin  and  purpurin,  and  they  conse- 
quently are  durable. 

The  scarlet  and  the  carmine-toned  lakes  are  intended 
to  imitate  the  true  carmine  obtained  from  cochineal. 
This  they  cannot  do  in  reality,  for  if  placed  side  by  side, 
the  cochineal  carmine  is  the  richer  by  far  for  a  few  days. 
Change  that  to  a  few  weeks,  and  the  alizarin  carmine  will 
become  the  brighter  and  richer  of  the  two.  An  expos- 
ure of  six  weeks  will  do  that.  v 

These  lakes  (the  whole  range  of  them)  are  useful  in 
either  oil,  japan,  varnish,  or  distemper;  in  distemper, 
however,  all  are  less  permanent  than  they  are  in  the  other 
vehicles,  as  these  protect  them. 

Certain  of  the  proprietary  reds  used  in  coach  work  are 
remarkably  well-made  goods,  and  but  for  the  impropriety 


126  MODERN  PIGMENTS 

of  giving  some  of  these  a  free  advertisement,  and  also  of 
doing  sundry  others,  probably  as  good,  an  injustice  by 
not  also  naming  them  —  the  author  does  not  claim  to 
have  tested  them  all  —  therefore  he  refrains  from  nam- 
ing any.  The  mention  of  their  existence  is  sufficient, 
because  the  reader  is  made  aware  of  their  character. 

INDIAN  LAKE 

Properties  and    Uses 

Some  few  decorators  and  artists  still  cling  to  this  lake, 
but  there  are  no  good  reasons  why  its  use  should  not  be 
abandoned  altogether.  It  is  universally  admitted  to  be 
very  inferior  to  the  madder  lakes,  but  it  is  somewhat 
more  permanent  than  the  cochineal  lakes,  and  that 
is  probably  why  some  continue  its  use.  The  excuse 
is  a  very  lame  one.  It  is  far  less  brilliant  than  and 
very  much  inferior  in  durability  to  the  madder  lakes  of 
corresponding  tone. 

Indian  lake  is  a  lac  of  a  resinous  character  produced 
by  various  plants  in  the  East  Indies.  These  are  punc- 
tured by  the  larva  of  the  Coccus  Lacca,  and  the  result 
of  the  puncture  is  the  resinous  lac,  from  which  the 
color  is  derived.  It  varies  in  color  according  to  the 
plant  from  whence  it  is  derived.  This  resin  is  pounded 
in  water,  the  water  becomes  red,  and  after  having 
been  boiled  down,  the  residue  made  by  the  evaporation 
is  the  crude  lac  dye.  This  is  dried  and  made  into 
cakes.  The  above  suffices  to  indicate  its  provenance 
and  character. 

Its  use  is  lessening  daily,  and  it  is  only  a  question  of 
time  when  it,  as  well  as  many  other  pigments  which 
have  been  useful  in  the  past, —  for  want  of  better, —  will 
be  known  no  more,  except  in  history. 


RED  PIGMENTS  127 

CARMINE  AND  COCHINEAL. 

History  and  Production 

Carmine  is  said  to  have  been  discovered  by  a  Florentine 
monk,  who,  while  he  was  engaged  in  the  preparation  of 
some  medicine  in  which  cochineal  was  introduced, 
observed  a  bright  red  precipitate.  For  the  sale  of  this 
red,  his  monastery  afterwards  became  famous. 

Carmine  is  a  coloring  principle  found  in  the  body  of  a 
small  insect  called  cochineal.  It  is  said  that  the  water 
used  in  its  manufacture  has  a  great  deal  to  do  with  the 
beauty  and  brilliancy  of  the  pigment  obtained  from  it. 
Otherwise  its  extraction  is  a  simple  affair. 

The  following  will  explain  in  a  few  words  how  it  is 
extracted.  Take  one  pound  of  powdered  cochineal,  and 
add  four  or  five  drams  of  subcarbonate  of  soda  or 
potash.  When  this  has  been  boiled  in  soft  water  for  a 
quarter  of  an  hour,  add  eight  or  ten  drams  of  alum. 
After  the  solution  has  been  effected,  take  the  receptacle 
from  the  fire,  draw  it  off  into  clean  vessels,  and  after  it 
has  stood  for  about  a  week,  the  carmine  will  be  found 
deposited  at  the  bottom.  This  deposit  must  be  carefully 
dried,  and  then  it  is  ready  for  use. 

There  are  many  other  methods  of  extracting  carmine, 
but  the  above  is  as  simple  as  any,  and  will  suffice. 

Properties  and    Uses 

Carmine  is  a  very  brilliant  color  when  well  made. 
Alas!  it  cannot  long  resist  the  action  of  a  strong  light, 
and  it  will  quickly  fade  away  if  so  exposed.  Its  place 
is  being  rapidly  taken  by  the  madder  lakes,  and  while  it 
must  be  admitted  that  these  are  not  so  brilliant  at  the 
start,  in  a  very  few  days  they  appear  the  more  brilliant 
of  the  two. 


128  MODERN  PIGMENTS 

It  is  very  rich  as  a  glazing  color  over  English  vermilion, 
and  is  still  used  for  that  purpose  by  the  carriage  painters, 
although  even  for  that  purpose  many  of  them  have  sub- 
stituted a  madder  lake  of  similar  tone,  as  most  individuals 
prefer  a  mediocre  stability  to  a  short-lived  brilliancy. 

It  is  a  pity  that  such  a  fine  red  should  be  so  fugitive, 
and  for  that  reason  painters  who  value  their  reputations 
must  go  slow  about  its  use,  and  had  better  let  it  alone. 

There  are  many  other  reds  that  can  be  found  listed  in 
artists'  supply  store  catalogues,  but  many  of  these  can  be 
placed  and  belong  to  the  reds  described,  and  the  rest  are 
for  use  in  padding  the  lists;  most  of  them  are  absolutely 
useless  even  to  decorators  and  artists.  Red  ochers  are 
sold  under  that  name  and  a  dozen  others.  They  are 
natural  reds,  the  same  as  the  yellow  ochers.  All  such 
should  be,  and  in  fact  are,  most  advantageously  displaced 
by  the  artificially  made  Venetian  reds,  as  these  are  uni- 
form, and  have  the  color  better  fixed  than  the  natural 
ocher  reds,  and  possess  the  same  range  of  color  tones. 
There  is  no  object  in  retaining  the  former;  they  cumber 
the  red  list  uselessly.  Many  are  little  better  than  mortar 
colors,  and  are  decidedly  poor  in  working  qualities. 


CHAPTER  XI 

GREEN    PIGMENTS 

CHROME  GREENS 

CHROME  GREEN  is  the  one  green  which  is  most  used  by 
house  painters  and  decorators,  and  for  this  reason  it  is 
given  first  place  here.  It  has  been  the  aim  to  notice  the 
various  pigments  in  a  group  according  to  prominence. 
It  is  not  possible  to  do  this  in  every  instance.  Frequently 
it  is  hard  to  choose  between  two  which  seem  to  have 
equal  claims  for  prominence.  In  this  instance,  it  is 
regrettable  that  there  is  no  better  one  to  head  the  list. 

Chemistry  and  Preparation 

Chrome  green  is  a  compound  pigment,  not  only  in  the 
sense  of  many  other  pigments  of  various  substances  com- 
bined together,  but  also,  in  that  it  is  a  secondary  color; 
in  other  words,  that  it  is  of  two  other  distinct  colors  which 
when  combined  form  greens,  viz.,  Prussian  blue  and 
chrome  yellow.  It  can  'be  made  by  a  simple  mixture 
and  triturating  the  pair. 

In  color  works  it  is  never  so  made.  In  these  estab- 
lishments they  take  the  equivalents  in  chemicals  of  both 
these  colors  and  dissolve  into  solutions.  Then  they  mix 
these  together  in  large  vats,  and  the  green  is  precipitated. 
This  green  is  what  is  known  as  chrome  green  in  the  United 
States.  By  this  process,  it  is  claimed  that  the  color  thus 
produced  is  more  intimately  mixed  and  incorporated. 
Besides,  it  gives  every  manufacturer  room  to  make  the 

129 


130  MODERN  PIGMENTS 

claim  that  by  his  particular  method  of  handling  and  pre- 
cipitating, he  is  able  to  fix  the  coloring  matter  much 
better  than  any  other  maker  has  ever  been  able  to  do, 
and  also  claim  superior  permanency  for  the  same  reason. 

Be  that  as  it  may,  there  is  one  sure  thing,  and  that  is, 
that  certain  chrome  greens  are  certainly  much  more 
permanent  than  others.  Some  retain  their  tone  much 
longer  than  others,  remaining  of  a  decided  green  after 
others  of  equal  strength  of  coloring  matter  have  badly 
faded.  A  number  seem  to  fade  very  soon  after  applica- 
tion; others  again,  like  some  widows,  wait  a  reasonable 
time  before  changing  their  dresses. 

After  the  chrome  has  been  precipitated,  the  supernatant 
water  is  drawn  off;  the  pulp  green  is  put  into  filtering 
cloths  and  in  presses  to  free  it  of  water.  The  pressed 
cakes  are  taken  to  the  drying  room  and  left  there  until 
bone  dry,  after  which  they  are  taken  out,  broken  up  and 
pulverized  in  the  mills,  and  are  then  ready  for  sale  as  dry 
chrome  green;  or  for  grinding,  in  oil,  japan,  varnish,  or 
water,  for  the  various  purposes  for  which  it  is  adapted 
and  wanted. 

What  has  been  written  above,  applies  to  the  manu- 
facture of  pure  chrome  greens;  but  pure  chrome  greens 
are  seldom  found  in  the  market. 

Owing  to  their  great  covering  properties,  and  amount 
as  well  as  strength  of  coloring  matter,  and  their  great 
opacity,  there  is  really  no  absolute  necessity  for  their 
absolute  purity.  The  reason  for  this  is  that  green  is 
seldom  employed  for  the  making  of  tints,  as  are  most  other 
colored  pigments.  Green  is  used  mostly  as  color  by  itself 
for  the  solid  painting  of  blinds  for  windows,  wagon  beds, 
implements,  iron  fences,  etc.  A  chrome  green  contain- 
ing only  20  to  25  per  cent  of  actual  chrome  green,  when 
it  has  been  properly  prepared  upon  a  good  base,  will 


GREEN  PIGMENTS  131 

cover  solidly  in  one  coat  any  other  color  over  which  it  is 
painted,  be  it  black  or  white.  It  would  be  a  waste,  there- 
fore, to  use  100  per  cent  of  color  chrome  green  to  do  what 
20  per  cent  of  it  will  do  as  well.  The  100  per  cent  green 
might  possibly  cover  a  trifle  more,  as  it  could  be  thinned 
more;  but  as  no  one  cares  to  apply  too  thin  a  color,  even 
that  would  not  amount  to  anything,  and  the  assertion 
can  safely  be  made  that  one  pound  of  20  per  cent  green 
will  cover  as  much  as  one  pound  of  100  per  cent. 

Therefore  by  common  consent  all  color  manufacturers 
put  out  a  chrome  green  containing  three  parts  of  base  to 
one  part  of  chrome  green.  This  mixture  then  contains 
25  per  cent  of  absolutely  pure  chrome  green. 

The  base,  of  whatever  nature  it  may  be  or  in  whatever 
proportion  it  is  used,  is  always  added  to  the  chemical 
solutions  just  at  the  moment  of  their  being  thrown  into 
the  vats  and  before  the  color  is  precipitated.  The  base 
and  the  color  are  precipitated  together.  This  insures 
uniformity. 

Nearly  all  the  chrome  greens  are  sold  under  some  pro- 
prietary name,  such  as  Crylight,  Marseilles,  Sylvan, 
Emerald,  French  Imperial,  and  a  host  of  others  entirely 
too  numerous  to  mention;  but  whatever  their  name  may 
be,  they  are  all  reduced  chrome  greens  and  belong  to  the 
class  just  described.  None  contain  over  25  per  cent  of 
actual  color  in  their  composition. 

When  chrome  green  is  used  for  the  purpose  of  making 
tints  with  other  pigments,  either  white  or  colored,  the 
strictly  pure  greens  should  be  used,  because  there  they  are 
the  more  economical.  Such  greens  can  be  bought,  but 
they  are  in  little  demand  aside  from  printing-ink  manu- 
facturers, etc.  Many  painters  make  pea  greens,  olives, 
and  the  various  light-toned  tints  of  those  and  other  greens 
from  ocher  chrome  yellows,  Prussian  blues,  etc.,  which 


132  MODERN  PIGMENTS 

they  compound  without  the  use  of  any  chrome  green. 
Hence  the  pure  greens  are  not  always  to  be  found  at 
paint  supply  stores,  because  the  demand  for  them  is  very 
slight. 

All  manufacturers  do  not  use  the  same  base  for  the 
purpose  of  reducing  the  pure  chrome  green  to  the  com- 
mercial basis  of  25  per  cent,  and  this  of  itself  accounts  for 
the  difference  found  in  their  working  qualities.  Barytes 
is  that  which  is  most  commonly  used  for  the  purpose, 
either  alone  or  in  conjunction  with  others.  Gypsum 
makes  the  best  base  for  that  purpose,  as  it  seems  to  hold 
up  the  color  better,  and  it  also  works  better  under  the 
brush.  Whiting  is  used  extensively  also;  and  added  to 
either  barytes  or  gypsum  to  make  the  paste  smoother 
in  texture,  it  also  helps  out  in  the  better  brushing  out  of 
the  paint. 

Properties   and    Uses 

Chrome  greens  come  in  two  tones;  and  accordingly  as 
it  approaches  to  one  or  the  other  of  these  two,  the  green 
is  so  classed.  The  two  tones  are  known  as  the  blue  greens 
and  its  opposite  —  the  yellow  greens.  In  some  of  its  blue 
shades,  chrome  green  approaches  somewhat  to  the  tone 
of  the  Paris  or  emerald  green.  There  is  a  wide  range 
to  be  found  in  the  tones  between  a  very  pale  yellow  green 
and  a  very  deep  blue  green  which  covers  the  whole 
gamut  and  chromatic  scale  of  the  green  tones.  Each  of 
these  two  groups  of  green  has  some  uses  to  which  it  is 
better  adapted  than  the  other.  As  a  rule,  the  yellow- 
toned  greens  are  stronger  in  coloring  matter  than  those 
of  a  corresponding  depth  in  the  bluish  ones. 

One  peculiarity  that  belongs  to  all  chrome  greens,  but 
in  a  much  stronger  degree  in  the  blue  than  in  the  yellow 
ones,  is  that  no  matter  how  carefully  they  may  have 


GREEN   PIGMENTS  133 

been  made,  if  there  is  any  supernatant  linseed  oil  when 
a  can  of  chrome  yellow  is  cut  open  the  oil  shows  up 
tinted  with  blue  as  if  the  blue  had  separated  from  the 
yellow.  This  property  is  inherent  and  does  not  hurt  it. 
The  necessary  trituration  of  the  color  before  using  it  will 
remedy  this  condition  and  reincorporate  the  trifling 
amount  of  dissolved  Prussian  blue. 

Some  of  the  well-made  chrome  greens  are  fairly  per- 
manent ;  but;  as  any  one  may  well  surmise,  anything  that 
would  destroy  the  color  of  Prussian  blue  —  such  as  lime 
or  other  caustic  substances  —  will  also  destroy  that  color 
in  the  chrome  green  combination.  Sulphureted-hydro- 
gen  gases  which  affect  chrome  yellow,  will  in  the  same 
manner  destroy  the  color  of  chrome  yellow  in  the  com- 
position of  the  green.  So  these  greens  have  to  carry  a 
double  load  of  liability  to  being  injuriously  acted  upon. 

Notwithstanding  that  chrome  green  is  anything  but 
absolutely  permanent,  to  all  intents  and  purposes  it  is 
sufficiently  so,  that,  for  want  of  a  better,  it  may  be  fairly 
depended  upon  for  many  situations  and  certain  condi- 
tions. 

It  is  used  by  all  classes  of  painters,  in  oil,  in  japan  or 
varnish,  and  in  enameling  or  japanning  works.  It  is 
also  very  useful  in  distemper  work  if  care  is  taken  in 
mixing  it  that  none  of  its  incompatibles  be  compounded, 
or  it  would  then  surely  fail. 

In  whatever  vehicle  it  is  used,  it  is  contra-indicated 
if  it  is  subject  to  any  of  the  influences  which  would  act 
injuriously  upon  either  chrome  yellow  or  Prussian  blue  — 
as  under  the  heading  of  either  of  those  colors,  this  is 
fully  given,  and  it  is  unnecessary  to  repeat  it  here. 

Chrome  green  and  all  the  proprietary  greens  —  which, 
as  we  have  seen,  are  all  chrome  greens  —  come  in  several 
shades.  Manufacturers  pack  it  up  in  cans  as:  Extra 


134  MODERN  PIGMENTS 

Light,  Light,  Medium,  Dark,  or  Extra  Dark,  each  of  which 
makes  an  entirely  distinct  set  of  tints  with  a  white  base. 

To  ascertain  the  value  of  a  chrome  green,  it  is  proper 
to  make  a  scale  test  of  it  alongside  one  of  the  same  grade 
that  is  of  known  standard.  With  that  test  one  can 
readily  determine  the  amount  of  coloring  matter  it 
contains. 

One  should  never  take  a  strictly  pure  green  to  judge 
values,  and  expect  one  of  only  25  per  cent  of  claimed  and 
acknowledged  purity  to  come  up  to  it.  If,  however,  four 
times  as  much  of  the  commercial  grade  is  taken  as  is  of 
the  strictly  pure,  the  tints  made  should  be  equal. 

The  reader  will  find  full  directions  of  how  to  make  these 
tests  at  the  end  of  Chapter  VI  under  the  heading  Chrome 
Yellow. 

GREEN  OXIDE  OF  CHROMIUM 

Properties  and  Uses 

The  green  oxide  of  chromium  is  known  to  the  artists 
and  decorators  of  the  world  under  many  names,  and  in 
reality  is  the  only  green  entitled  to  the  name  of  chrome 
green,  for  it  is  that.  But  what  we  know  under  that  name 
in  the  United  States  is  a  different  pigment,  which,  while  it 
is  not  entitled  to  it,  is  the  only  one  here  known  by  that 
name. 

Life  is  too  short  to  start  a  crusade  and  to  make  a 
quixotic  fight  against  windmills  —  which  it  would  be  if 
the  effort  were  made  to  change  the  name — and  it  is  simply 
accepted  through  sheer  compulsion;  it  cannot  be  helped. 

Green  oxide  of  chromium  is  a  good  enough  name  if  it  is 
a  bit  long  in  the  saying;  as  it  is,  it  is  so  seldom  used  that 
it  matters  but  little  anyway.  Many  of  the  proprietors 
of  paint  supply  stores  would  be  puzzled  if  one  was  to 
call  for  it,  and  would  not  know  what  was  meant. 


GREEN   PIGMENTS  135 

Owing  to  its  limited  use,  but  little  need  be  said  of  its 
manufacture.  The  intricate  processes  of  manufacture 
make  it  an  expensive  pigment,  and  that  alone  will  always 
prevent  its  use,  even  if  it  possessed  much  better  qualities 
than  those  which  are  inherent  in  it.  So  that  with  the 
cheap  imitation  chrome  greens,  which  cover  better  and 
cost  ever  so  much  less,  there  is  little  danger  of  it  ever 
coming  into  popular  use. 

Two  distinct  processes  are  used  in  its  manufacture, 
and  these  are  known  as  the  dry  and  the  wet.  Accordingly 
as  it  is  made  by  the  wet  or  the  dry  process,  this  pigment 
is  either  transparent  or  opaque.  The  latter  is  the  usual 
condition  under  which  it  is  to  be  found  in  artists'  tube 
colors.  When  made  by  the  wet  process  the  sesquioxide 
is  thrown  down,  and  that  makes  it  transparent.  It  is 
therefore  useful  both  as  a  solid  color  for  opaque  paint- 
ing, or  the  transparent  for  glazing  purposes.  This  pig- 
ment is  somewhat  more  permanent  than  the  so-called 
American  chrome  green  goods  which  are  known  and  sold 
here  as  chrome  green,  and  it  can  be  mixed  with  most  of 
the  permanent  pigments. 

COBALT  GREEN  (ZINC  GREEN) 

Properties  and  Uses 

This  valuable  pigment  deserves  a  more  extensive 
use  than  that  which  it  has  so  far  received  in  the  United 
States.  In  Europe,  especially  in  England,  France,  and 
Germany,  it  is  much  more  popular  than  it  is  here.  In 
America,  it  is  mainly  found  in  tubes  for  artists'  use,  and 
is  seldom  ever  offered  in  any  other  shape.  It  is  imported, 
and  if  manufactured  in  the  United  States  the  author  has 
never  heard  of  it.  There  is  no  reason  why  it  should  not 
be  made  here.  As  I  am  not  familiar  with  its  preparation, 


136  MODERN  PIGMENTS 

I  give  the  following  extract  from  Church's  "Chemistry  of 
Paints": 

"It  has  long  been  known  that  the  oxide  or  a  salt  of 
zinc  moistened  with  a  solution  of  cobalt  nitrate  and  then 
strongly  heated  before  the  blowpipe  gives  a  porous  mass  of 
a  beautiful  green  hue.  This  compound  or  mixture  of  the 
oxides  of  zinc  and  cobalt  may  be  prepared  by:  1st. 
Precipitating  with  an  alkaline  carbonate  a  mixture  of  the 
nitrates  of  cobalt  and  zinc,  and  then  strongly  heating 
(after  washing)  the  precipitate  formed  thereby;  2d, 
Making  a  paste  of  zinc  oxide  and  water,  and  adding  a 
solution  of  nitrate  or  sulphate  of  cobalt  or  roseo-cobaltic 
chloride;  the  mass  is  then  dried,  calcined  at  a  dull  red  heat, 
thrown  into  water,  ground,  washed  and  dried.  Method 
No.  2  gives  a  finely  colored  product,  the  depth  of  hue 
being  proportional  to  the  percentage  of  cobalt ic  oxide. 
If  the  latter  oxide  amounts  to  one  third  that  of  zinc,  the 
color  is  a  very  deep  bluish  green;  with  no  more  than  one 
sixth,  the  color  is  still  rich.  Some  specimens  do  not  con- 
tain more  than  one  twentieth,  —  occasionally  even  less 
of  cobalt  oxide,  —  and  yet  they  are  far  from  pale.  An 
excellent  deep  sample  contained  12  per  cent  of  cobalt 
oxide. 

"When  properly  made,  cobalt  green  is  a  pigment  of 
great  beauty  and  power.  The  deeper  tones  of  cobalt  green 
are  almost  transparent  in  oil.  The  pigment  works  well, 
is  quite  permanent,  and  has  no  action  upon  other  pig- 
ments. Cobalt  green  is,  in  fact,  one  of  the  two  rare  pig- 
ments which  are  at  once,  chemically  and  artistically 
perfect.  It  must  be  admitted  that  it  is  almost  exactly 
imitated  by  a  mixture  of  viridian  and  artificial  ultramarine 
with  a  little  zinc  white. 

"Cobalt  green  is  again  coming  into  artistic  use,  as  it  is 
equally  well  adapted  for  all  methods  of  painting.  It 


GREEN   PIGMENTS  137 

was  discredited  awhile  by  the  inferiority  of  the  product 
obtained  by  Rinmann's  original  process  (No.  1  above)." 

It  ought  not  to  be  an  expensive  pigment,  and  if  manu- 
factured here  upon  a  large  scale  its  cost  would  be  low 
enough  for  use  in  general  painting. 

Sometimes  the  green  is  prepared  by  precipitating  a 
cobalt  salt  with  an  alkaline  arseniate  or  phosphate,  and 
then  heating  the  precipitate  with  zinc  white. 

Cobalt  green,  as  was  seen  above,  is  more  or  less  trans- 
parent according  to  its  depth  of  tone.  The  lighter  tones 
are  much  more  opaque,  and  these  would  be  the  best  for 
solid  painting,  but  the  deep  ones  used  as  a  glazing  coat 
over  other  greens  give  rich  effects.  This  pigment  is  good 
in  any  of  the  usual  vehicles,  and  it  is  hoped  it  will  become 
better  known  to  the  general  trade.  It  would  be  invaluable 
to  the  carriage  and  car  trade;  and  decorators  should  use 
it  more  in  interiors,  where  it  is  free  from  attacks  of  the 
deadly  enemies  of  most  other  greens, 

VIRIDIAN 

Properties  and  Uses 

Again  recourse  is  had  to  the  same  source  for  informa- 
tion concerning  viridian.  Church  says  of  it: 

"About  eight  parts  of  crystallized  boracic  acid  and 
three  parts  of  potassium  bichromate  are  thoroughly 
mixed  and  calcined.  The  mass  so  obtained  is  treated  with 
cold  water  and  washed  by  decantation,  ground  wet, 
washed  with  hot  water  and  carefully  dried.  The 
product  is  an  hydrated  chromium  sesquioxide  in 
which  a  variable  amount  of  the  boracic  constituent 
frequently  remains.  Viridian,  however,  is  essentially 
an  hydrated  sesquioxide  of  chromium,  having  the 
formula  of  Cr2032H2O. 


138  MODERN  PIGMENTS 

"The  color  of  viridian  is  a  very  deep  bluish  green  of 
great  purity  and  transparency.  It  furnishes  with  aureo- 
lin  on  the  one  hand  and  with  ultramarine  upon  the  other 
an  immense  number  of  beautiful  hues  adapted  to  repre- 
sent the  colors  of  vegetation  and  water. 

"It  is  quite  unaffected  by  sunlight  or  sulphureted 
hydrogen,  and  it  has  no  eyil  action  of  its  own  upon  other 
pigments.  Moreover,  it  can  be  safely  used  with  all  the 
painting  media  and  upon  all  kinds  of  painting  grounds." 

It  should  be  more  extensively  used  by  the  carriage 
trade,  as  it  is  just  the  sort  of  pigment  that  is  needed  for 
a  permanent  glaze. 

It  is  chiefly  imitated  by  compounds  of  chrome  yellows 
and  blues,  but  such  are  worthless;  they  possess  neither 
the  brilliancy  nor  the  permanency  of  viridian. 

Its  use  is  confined  to  the  artist's  palette  and  to  the 
decorators. 


CHAPTER   XII 

GREEN   PIGMENTS     (Continued) 

TERRE  VERTE 

History  and  Production 

THERE  are  to  be  found  in  various  parts  of  the  world,  in 
the  New  as  well  as  in  the  Old,  certain  earths  having  a 
variety  of  greenish  tones.  These  earths  vary  greatly  in 
their  composition,  as  one  might  well  suppose,  and  in 
consequence  of  this  are  diversified  in  their  respective 
colors. 

Terre  verte  was  made  use  of  in  the  earliest  attempts 
at  decoration,  and  is  found  upon  ancient  Roman 
wall  paintings.  The  prepared  pigment  itself  has 
been  discovered  in  pots  in  the  ruins  of  the  city  of 
Pompeii. 

None  of  the  various  shades  of  this  pigment  are  at  all 
vivid,  and  all  partake  of  the  tertiary  order. 

It  is  prepared  for  use  in  much  the  same  manner  as  was 
indicated  for  ocher  and  the  other  earth  pigments  which 
already  have  been  under  notice  —  by  washing  or  levi- 
gating to  free  it  from  its  heavier  impurities,  and,  after- 
wards, separating  into  various  grades,  then  drying, 
pulverizing,  etc. 

The  following  analysis,  made  by  A.  H.  Church,  is  that 
of  a  sample  from  Monte  Baldo  in  Italy.  It  shows  that 
terre  verte  is  allied  to  the  hornblendes,  and  that  it  is  a 
silicious-ferric  product : 

139 


140  MODERN  PIGMENTS 

Analysis  of  Terre  Verte 

Water  given  off  at  100°  C.       ......  4.1 

Water  given  off  at  red  heat 4.2 

Ferric  oxide  (Fe2O3)      20.3 

Ferrous  oxide  (Fe20) 2.6 

Alumina      1.7 

Lime 1.1 

Magnesia 5.6 

Potash      .    .    .    ; 6.4 

Soda         2.3 

Silica        52.0 

From  the  composition  shown  by  the  analysis,  a  person 
can  at  once  infer  that  terre  verte  is  little  subject  to  change, 
as  all  its  constituents  are  themselves  the  product  of  any 
and  all  possible  change,  and  incapable  of  any  further 
ones. 

Terre  verte  is  only  semi-opaque  in  character,  and  there- 
fore covers  indifferently  well  when  mixed  with  linseed 
oil  or  varnish.  Its  use  in  oil  is  limited  to  the  producing 
of  certain  neutral-toned  greenish  hues  with  a  white  base. 
It  possesses  the  quality  of  absolute  permanency,  and  pro- 
longs the  life  of  white  lead  associated  with  it  in  the  making 
of  tints.  It  does  this  because  of  its  power  of  absorbing 
large  quantities  of  linseed  oil,  and  acts  in  many  respects 
as  do  all  the  silicate  earths. 

It  is  chiefly  used  in  water  or  distemper.  In  distemper 
it  covers  well,  and  its  neutral  tones  and  that  of  its  tints 
are  much  better  fitted  for  mural  painting  than  it  is  in  oil. 

Some  fine  samples  of  it  have  been  found  in  various 
parts  of  New  England,  and  many  manufacturers  grind  it 
under  their  proprietary  names.  Manufacturers  of  mixed 
paints  can  also  use  it  to  good  advantage  for  certain  tints 
on  acbount  of  its  imparting  good  wearing  qualities  and 
because  of  its  relative  cheapness. 


GREEN   PIGMENTS  141 

VERDIGRIS 

Chemistry   and   Preparation 

Verdigris  is  the  basic  preparation  of  copper.  It  is  a 
permanent  bluish  green,  and  is  made  in  large  quantities 
in  Southern  France,  where  the  city  of  Grenoble  is  head- 
quarters for  its  distribution. 

It  is  produced  from  copper  sheets  or  plates  upon  which 
the  grape  pomace,  obtained  from  the  wine-presses  so 
abundant  in  that  section,  has  been  spread.  By  fermen- 
tation, the  acetic  acid  is  combined  with  the  copper,  and 
forms  upon  the  surface  a  green  rust  which  is  verdigris 
or  the  subacetate  of  copper.  It  can  be  manufactured 
in  various  ways,  but  as  the  use  of  that  pigment  is  becom- 
ing more  restricted  every  year,  and  as  the  description  of 
the  processes  would  require  more  space  than  the  little 
usage  that  is  made  of  it  warrants,  the  above,  which  is  the 
principal  method  of  obtaining  it,  will  suffice,  with  this 
additional  note,  that  the  raw  product  thus  obtained  is 
afterwards  manipulated  to  free  it  from  impurities.  It  is 
then  crystalline,  and  in  that  shape  it  appears  upon  the 
markets  of  the  world. 

Verdigris  is  a  perfectly  transparent  pigment,  and  its 
chief  use  in  decorative  work  is  where  that  effect  counts 
heavily. 

Its  main  use  to-day  is  as  an  ingredient  in  many  anti- 
fouling  preparations  for  the  painting  of  ships'  hulls 
below  the  water  line,  especially  for  the  copper  sheathing 
placed  upon  the  bottoms  of  wooden  vessels.  It  is  claimed 
that  barnacles  and  other  sea  pests  which  love  to  attach 
themselves  to  ship-bottoms  —  thereby  causing  in  the 
roughness  of  their  uneven  accumulations  an  impediment 
that  results  in  more  friction  and  lessened  speed  when  plow- 
ing through  the  water  —  that  said  pests  will  not  attach 


142  MODERN  PIGMENTS 

to  vessels  whose  bottoms  have  been  painted  with  it. 
The  poisonous  character  of  that  pigment  may  have  some- 
thing to  do  with  that;  possibly  it  kills  them.  At  any 
rate,  their  number  is  greatly  lessened  when  such  bottoms 
have  been  painted  with  verdigris.  Sulphureted- 
hydrogen  gases  darken  verdigris.  It  is  not  safe  nor 
suitable  in  any  way  to  use  it  in  water  colors,  nor  is 
its  use  in  oil  desirable,  although  when  mixed  in  that 
vehicle  it  is  at  its  best. 

It  is  poisonous,  and  while  not  of  as  violent  a  character 
in  that  regard  as  that  other  copper-base  pigment,  Paris 
green,  hereafter  described,  it  is  bad  enough  in  that  respect 
even  for  use  in  making  a  successful  suicide.  One  must 
exercise  some  caution  with  it. 

The  use  of  this  pigment  has  been  replaced  by  that  of 
other  greens,  and  it  is  almost  exclusively  confined  to  anti- 
fouling  paint  for  ship-bottoms. 

It  is  still  used  as  a  glazing  color  by  a  few  old-fashioned 
carriage  painters. 

MALACHITE,  OR  GREEN  VERDITER 

Properties  and  Uses 

Under  the  name  of  malachite,  a  natural  green 
carbonate  of  copper  has  been  a  long  time  in  use  as  a 
pigment.  It  is  mined  in  various  parts  of  the  world, 
freed  from  its  impurities,  and  treated  in  sundry  ways. 
Its  formula  is  CuCo3CuH2O2.  It  resembles  in  composition 
the  azurite  or  blue  verditer,  but  contains  less  of  the 
copper  carbonate. 

It  is  fairly  permanent;  but  acquires  a  dull  brownish 
hue,  due  to  the  darkening  of  the  linseed  oil;  is  not 
safe  as  a  water  color,  therefore  inadmissible  for  dis- 
temper work. 


GREEN   PIGMENTS  143 

It  is  so  seldom  used  now,  even  by  artists,  that  it  will 
be  cut  off  with  the  above  mention  and  with  a  parting 
warning  for  paint  students  to  leave  it  alone.  It  possesses 
no  peculiarity  of  tone  but  such  as  can  be  obtained  by  the 
use  of  less  dangerous  pigments  which  can  be  depended 
on  as  having  greater  permanency. 

EMERALD,  OR  PARIS  GREEN 

Chemistry,  Preparation,  and  Uses 

Paris  green  is  the  name  under  which  this  pigment  is 
best  known  in  the  United  States.  It  is  a  beautiful,  most 
rich  and  brilliant,  transparent  green,  but  for  all  its  beauty, 
its  violent  poisonous  properties  unfit  it  for  the  use  of  the 
house  painter,  and  it  is  only  with  the  utmost  care  that  it 
should  be  employed  by  the  coach  painter  as  a  finishing 
glaze.  There  is,  of  course,  nothing  like  it  for  this  purpose, 
and  hence  it  is  that  one  may  be  excused  in  taking  some 
risk  in  its  application.  With  a  great  deal  of  care  and  by 
the  wearing  of  a  sponge  at  the  nostrils  during  its  mixing 
and  manipulation,  the  danger  is  reduced  to  a  minimum. 
It  affects  some  painters  more  injuriously  than  others. 
Some  men  can  never  work  with  it  without  it  making  them 
sick;  such  should  never  use  it. 

Its  use  as  a  glazing  color  in  vehicles  is  questionable,  to 
say  the  least.  For  a  time,  while  it  is  protected  by  good 
coats  of  varnish,  it  may  be  safe  enough.  But  when  the 
varnish  decays,  and  is  not  promptly  replaced,  there  is  al- 
ways some  danger  of  particles  of  it  becoming  absorbed 
into  the  human  system,  especially  that  of  children. 
They  know  nothing  about  the  dangerous  qualities  of  the 
paint,  but,  attracted  by  its  beauty,  are  tempted  to  rub 
their  hands  over  it,  and  become  poisoned.  When  a 
death  occurs  (and  many  have  happened)  from  such  a 


144  MODERN  PIGMENTS 

cause,  what  useless  regrets  it  must  cause.     Therefore  the 
reluctant  advice  is  given  —  let  it  alone. 

This  pigment  is  cupric  aceto-arsenite,  and  is  permanent 
in  oil.  In  water  colors  it  is  not,  and  will  not  long  remain 
untarnished  in  impure  air. 

SCHEELE'S  GREEN 

Characteristics 

Scheele's  green,  or  cupric  arsenite,  is  another  copper  pig- 
ment. It  is  an  arsenite  of  copper,  and  its  process  of  manu- 
facture need  not  be  given,  as  it  has  become  obsolete.  In 
every  respect  but  one,  it  is  the  inferior  of  Paris  green, 
and  that  one  is,  that,  if  possible,  it  is  even  a  stronger 
poison.  As  is  the  case  of  many  another  pigment  for  which 
generations  of  painters  once  found  some  uses,  its  use  to- 
day is  about  nil,  and  it  has  been  replaced  by  others  bet- 
ter adapted  to  any  of  the  purposes  to  which  it  was  put 
by  old-time  decorators.  Its  place  at  the  tail  end  of  green 
pigments  is  well  deserved. 

Owing  to  its  frequent  mention  in  the  antiquated  litera- 
ture of  painters  of  the  eighteenth  century,  it  was  thought 
best  to  list  it  here,  simply  as  a  warning  example  and  to 
advise  against  its  use. 


CHAPTER  XIII 
BLUE  PIGMENTS 
ULTRAMARINE  BLUE 
Chemistry  and  Manufacture 

ULTRAMARINE  BLUE  is  one  of  the  conquests  of  science  of 
which  chemistry  may  well  be  proud.  As  a  pigment,  in  its 
natural  state  it  has  long  been  known.  It  can  be  obtained 
in  its  natural  state  and  condition  from  lapis-lazuli,  a 
semi-precious  stone.  There  is  little  danger  of  the  natural 
ultramarine  ever  becoming  a  dangerous  rival  of  the  arti- 
ficially prepared ;  and  if  it  had  to  be  extracted  from  the 
stone  now  as  formerly,  it  would  hardly  be  employed  as 
lavishly  as  it  is  to-day. 

Chemistry,  however,  revealed  its  composition;  and  ever 
since,  its  artificial  reproduction  has  permitted  it  to  be 
furnished  at  a  nominal  cost,  and  put  it  within  the  reach 
of  any  one,  whereas  formerly  royalty  only  could  have 
afforded  its  use  as  profusely  as  the  average  whitewasher 
could  do  to-day. 

The  processes  of  manufacturing  it  artificially  are  well 
known,  but  are  very  intricate;  and  until  within  a  com- 
paratively short  time,  this  pigment  was  imported  from 
Europe.  To-day  the  largest  works  in  the  world  are 
located  at  Newark,  N.  J.,  and  produce  as  good  an  article 
as  can  be  imported  from  anywhere.  All  the  raw  material 
that  is  used  in  the  manufacture  of  ultramarine  is  cheap; 
it  consists  of  kaolin,  or  china  clay,  silica,  sodium  sulphate, 

145 


146  MODERN  PIGMENTS 

sodium  carbonate,  sulphur,  charcoal,  and  rosin.  Calcined 
alum  is  sometimes  used  instead  of  kaolin.  After  heating 
the  ingredients  together  in  crucibles  and  then  cooling,  a 
greenish  porous  cake  is  found,  which  is  powdered 
and  roasted  (after  the  addition  of  sulphur)  for  several 
hours.  It  requires  several  powderings,  washings,  and 
dryings,  also  further  calcinations  to  develop  the  proper 
blue  color. 

To  prepare  it  for  use  requires  some  careful  manipula- 
tion. It  should  be  washed  with  water  free  from  lime, 
and  requires  to  be  finely  ground.  This  improves  the 
color  very  much,  and  any  soluble  impurities  are  removed 
by  these  washings. 

Properties   and    Uses 

The  range  of  color  is  great  in  this  pigment.  It  runs 
from  a  pure  blue  to  a  purple  blue,  and  some  shades  even 
border  upon  the  green,  and  are  called  green  ultramarines. 
However,  they  are  not  true  greens,  and  they  cannot  be 
listed  among  them.  The  shades  that  are  free  from  purple 
are  accounted  the  best,  and  for  the  purposes  of  the  painter 
are  certainly  superior,  as  it  is  very  easy  to  make  a 
purple-shaded  tint  from  a  blue  ultramarine,  but  it  is 
impossible  to  make  a  clean  blue  tint  from  a  purple 
tone  of  the  same. 

Ultramarine  should  never  be  mixed  with  white  lead 
for  the  making  of  tints,  on  account  of  the  sulphur  it  con- 
tains. When  it  is  used  with  a  white  base  for  that  pur- 
pose, zinc  white  is  much  the  best,  and  the  tone  of  the 
tints  will  be  cleaner  and  purer-looking. 

Sulphureted  hydrogen  does  not  affect  artificial  ultra- 
marine blue,  neither  does  lime  and  other  alkalies.  Weak 
acetic  acid  or  a  saturated  cold  solution  of  alum  does  affect 
it,  and  in  time  will  destroy  it.  It  may  be  called  a  per- 


BLUE  PIGMENTS  147 

manent  pigment,  as  sunlight  does  not  impair  it,  and  it  is 
useful  in  either  oil,  japan,  varnish,  or  distemper;  but  to 
be  safe,  it  should  not  be  used  in  connection  with  pigments 
that  have  acetic  acid  or  alum  in  their  composition.  It 
is  always  safe  when  used  alone  as  a  solid  color  or  with 
zinc  white  for  the  making  of  all  blue  tints. 

The  coach  painter  finds  good  use  for  it,  both  for  the 
painting  of  solid  surfaces  and  for  the  glazing  of  them 
with  the  transparent  kind.  As  this  pigment  is  usually 
prepared,  it  covers  fairly  well,  but  it  is  inferior  to  Prussian 
blue  in  this  regard. 

There  is  no  particular  standard  whereby  to  judge  of 
the  value  of  this  pigment  other  than  that  it  should  be  of 
good  blue  tone,  that  it  should  cover  well,  and  that  it 
should  be  strong  in  coloring  matter  for  the  solid  varieties; 
but  the  last  two  items  do  not  apply  to  the  kinds  of  it 
which  are  made  upon  a  transparent  base  and  which  are 
intended  for  glazing. 

It  is  also  extensively  used  for  house  painting,  in  the 
making  of  tints  with  zinc  white,  as  these  stand  well,  and 
remain  unaffected  by  sunlight,  which  cannot  be  said  of 
those  made  with  Prussian  blue. 

For  distemper,  it  is  also  very  useful  for  wall  work  and 
in  decorating. 

This  pigment  may  vary  a  good  deal  without  any 
intentional  adulteration  of  it.  But,  intentional  or  other- 
wise, it  should  be  up  to  some  good  sample,  which  can  be 
selected  and  preserved  for  comparison  with  it.  There- 
fore the  only  rule  to  judge  it  by,  and  the  one  point  upon 
which  all  would  agree,  is  purity  of  its  blue  tone  and 
brilliancy. 

It  comes  to  market  in  its  dry  state  in  boxes  containing 
28  pounds.  It  also  comes  ground  in  oil,  japan,  or  varnish, 
as  well  as  in  water  for  distemper  painting. 


148  MODERN  PIGMENTS 

PRUSSIAN  BLUE 

History  and  Chemistry 

This  pigment  really  deserves  to  be  placed  first  upon 
the  list  of  blues.  It  is  probably  used  the  most  of 
all  the  blues  by  painters  and  decorators,  but,  owing  to  its 
being  more  fugitive  in  sunlight  than  ultramarine,  it  was 
thought  best  to  give  it  as  second  on  the  list. 

Its  history  now  dates  back  nearly  two  centuries,  and 
its  discovery  was  accidental.  One  Diesbach,  in  1714, 
while  he  was  precipitating  a  solution  of  alum  to  obtain  a 
white  base  for  the  manufacture  of  lakes,  used  some  potash 
that  had  been  rectified  with  animal  oil,  and  instead  of 
precipitating  a  white  substance,  it  precipitated  a  blue  one. 
He  had  purchased  the  potash  from  a  man  named  Dippel, 
who,  having  been  informed  of  the  occurrence,  traced  it  to 
the  proper  cause  and  was  able  to  produce  Prussian  blue. 
The  process  was  kept  a  secret  as  long  as  possible,  but  in 
1724  it  was  discovered  by  Woodward,  and  by  him  made 
public. 

Its  manufacture  is  as  simple  as  can  be,  and  is  done  by 
various  processes,  the  necessary  agent  being  prussiate  of 
potash.  This  is  obtained  by  fusing  the  potash  of  com- 
merce with  blood  or  other  aninial  refuse.  After  careful 
preparation,  it  is  of  a  yellow  color.  It  is  added  to  another 
solution  made  from  two  parts  of  alum  and  one  part  of 
sulphate  of  iron,  the  mixture  filtered  and  allowed  to  settle. 
A  double  decomposition  ensues,  in  which  the  iron  com- 
bines with  the  potash  of  the  prussiate,  forming  a  sulphate 
of  potash,  while  the  prussiate  of  iron  is  thrown  down, 
the  sulphate  of  potash  being  held  in  solution. 

On  the  other  hand,  a  similar  decomposition  takes  place 
with  the  alum,  and  the  superabundant  carbonate  of 
potash  is  mixed  with  the  solution  of  prussiate  of  potash. 


BLUE  PIGMENTS  149 

By  this  means  a  sulphate  of  potash  is  formed,  and  the 
alumina  or  base  of  the  alum  is  precipitated.  These  two 
precipitates,  prussiate  of  iron  and  alumina,  are  produced 
at  the  same  instant  of  time  and  are  intimately  mixed, 
producing  a  substance  of  a  brilliant  and  intense  blue, 
the  Prussian  blue  of  commerce;  this,  of  course,  after  it  has 
been  well  washed  and  dried. 

Whatever  may  be  the  system  and  methods  of  manipu- 
lation,— and  these  may  differ  greatly,—  the  equivalents  of 
the  above  must  be  present  to  produce  Prussian  blue. 

Properties  and  Uses 

Prussian  blue  is  a  transparent  pigment  of  great  strength 
of  coloring  matter,  capable  of  absorbing  enormous 
quantities  of  linseed  oil.  On  account  of  the  fineness  of  its 
particles,  and  the  still  greater  fineness  which  can  be  given 
them  by  thorough  grinding,  Prussian  blue  is  held  a  long 
time  in  suspension  before  precipitating  in  that  vehicle. 

Plow  and  implement  manufacturers  use  it  to  paint  over 
polished  steel  parts  to  preserve  them  from  air  or  moisture, 
and  consequent  rust.  In  the  diluted  condition  in  which 
it  is  used  for  that  purpose,  it  is  thinned  out  in  the  pro- 
portion of  one  hundred  pounds  of  linseed  oil  to  one  pound 
of  the  pigment. 

One  may  well  wonder  at  the  strength  and  power  of 
coloring  matter.  A  pound  of  it  will  tint  a  ton  (2000 
pounds)  of  white  lead  to  a  decided  sky  blue. 

There  are  two  qualities  of  Prussian  blue,  which  may  be 
thus  described :  Quality  No.  1  is  very  good;  quality  No.  2  is 
good  for  nothing.  The  good  should  have  a  decided  blue 
tone  of  great  clearness;  that  is  the  only  tone  of  it  worth 
having.  The  other  has  a  purplish  or  dirty  blue-black 
tone,  and  no  amount  of  trying  to  doctor  it  up  will  help  any. 
The  tints  made  from  it  are  invariably  sickly,  miserably 


150  MODERN  PIGMENTS 

muddy-looking,  and  never  give  satisfaction.  Any  tint 
made  from  Prussian  blue  of  good  quality  and  a  suitable 
white  base  is  very  clear,  clean-toned,  and  fairly  permanent 
under  proper  conditions.  In  time  it  acquires  a  slightly 
greenish  hue,  but  much  of  this  is  due,  in  part  at  least,  to 
the  change  that  takes  place  in  the  oil.  When,  however, 
it  comes  in  contact  with  lime,  it  bleaches  entirely  away; 
even  the  tints  of  it  made  with  a  white  base  will  suffer. 
All  the  alkalies  have  the  same  property,  which  is  fatal  to 
it.  Therefore  it  is  unsuited  for  distemper  work,  especially 
when  the  walls  are  newly  plastered,  and  where  it  will  come 
in  contact  with  lime  which  has  lost  none  of  its  causticity. 

Soluble  and  Insoluble  Varieties 

There  are  two  distinct  varieties  of  Prussian  blue  that 
differ  only  in  that  one  is  soluble  in  water,  and  the  other 
is  not.  In  the  United  States  it  is  customary  to  designate 
as  Prussian  blue,  only  the  variety  which  is  insoluble  in 
water;  the  soluble  variety  being  better  known  as  Chinese 
blue  or  as  soluble  blue. 

CHINESE  OR  SOLUBLE  BLUE 

Properties  and  Uses 

Chinese  blue  is  only  a  variation  of  Prussian  blue.  It 
possesses  all  the  characteristics  of  the  former  with  the  one 
exception,  —  it  is  soluble  in  water  instead  of  insoluble. 
On  account  of  its  solubility,  it  is  seldom  used  for  distemper 
painting.  A  damp  handkerchief  laid  over  it  for  a  minute 
will  extract  color.  It  is  also  subject  to  the  same  vicissi- 
tudes, when  it  comes  in  contact  with  lime  and  other 
caustic  substances,  as  Prussian  blue. 

After  it  has  dried,  when  mixed  with  linseed  oil,  it  is  all 
right,  and  moisture  will  not  affect  it  as  long  as  the  linseed 


BLUE  PIGMENTS  151 

oil  is  undecayed.  Therefore  for  use  in  oil  it  is  probably  as 
good  as  the  insoluble  or  Prussian  blue.  But,  as  it  is 
identically  the  same  thing,  there  is  no  need  of  cumbering 
the  color  list  so  uselessly  as  with  a  separate  pigment. 
Prussian  being  the  same,  and  furthermore,  insoluble,  it  is 
the  better  of  the  two. 

As  soluble  blue,  it  has  uses  which  are  mainly  in  the 
preparation  of  bluing,  either  in  the  liquid  form  or  in  a  dry 
powder  for  laundry  purposes,  for  the  preparation  of  car- 
penters' crayons,  and  many  other  economical  purposes 
which  are  foreign  to  the  subject  matter  of  this  treatise, 
and  for  that  reason  need  not  be  related  here. 


CHAPTER  XIV 

BLUE  PIGMENTS  (Continued) 

COBALT  BLUE 

Manufacture,  Properties,  and   Uses 

UNDER  the  name  of  cobalt  blue  there  are  several 
substances  sold  which  claim  to  be  it.  The  best  known 
is  that  which  is  made  by  a  combination  of  cobalt  oxide 
and  alumina.  Thenard's  blue,  another  variety  of  it, 
is  a  cobalt  phosphate  on  an  aluminous  base. 

The  first  is  the  less  complicated,  and  can  be  produced 
by  calcining  a  well-triturated  mixture  of  aluminum- 
hydrate  and  cobalt-oxide.  The  greatest  care  must  be 
taken  that  the  material  used  in  the  preparation  of  this 
pigment  shall  be  free  from  iron  and  nickel;  these  sub- 
stances injure  the  purity  of  tone  and  the  brilliancy  of 
the  cobalt  blue. 

Cobalt  blue  is  a  permanent  pigment,  unaffected  by 
light,  moisture,  or  by  oxygen.  Cobalt  can  be  safely  used 
in  true  fresco,  as  it  is  unaffected  by  lime.  It  can  also  be 
safely  used  with  any  of  the  other  pigments.  It  is  not 
as  strong  in  coloring  matter  as  ultramarine  blue,  and  is 
decidedly  lighter  in  tone. 

Nineteen  twentieths  of  the  cobalt  blue  that  is  offered 
for  sale  in  the  United  States,  is  compounded  from  a  good 
quality  of  ultramarine  blue  and  an  admixture  of  zinc 
white,  so  that  its  shade  may  be  lightened  to  that  of  cobalt 

162 


BLUE   PIGMENTS  153 

blue,  and  of  which  this  makes  a  good  imitation.  This 
imitation,  in  fact,  is  so  close  that  even  an  expert  would 
have  difficulty  in  detecting  it.  To  all  intents  and  pur- 
poses, when  the  pigment  is  mixed  with  linseed  oil,  it  is 
fully  as  good  as  true  cobalt ;  but  if  used  in  distemper,  it  is 
subject  to  the  same  baneful  liabilities  which  have  been 
indicated  under  the  heading  of  that  pigment,  and 
instead  of  perfect  security,  which  the  true  pigment  would 
have  given,  there  are  the  usual  troubles  arising  from 
ultramarine. 

It  is,  therefore,  questionable  whether  it  will  pay  the 
painter  to  buy  this  as  long  as  there  is  no  assurance 
of  its  purity  to  be  had.  It  is  just  as  easy  to  make  it 
as  it  is  wanted;  it  is  simply  an  ultramarine  tint  which 
can  be  prepared  by  any  one  from  the  mixing  of  ultra- 
marine and  zinc  white. 

CERULEUM 

Properties  and    Uses 

Ceruleum  is  little  known  in  the  United  States.  Church, 
in  his  "  Chemistry  of  Paints,"  has  this  to  say  of  it: 

"When  oxide  of  tin  is  moistened  with  a  cobalt  nitrate 
solution  and  strongly  heated,  a  greenish  blue  mass  is 
obtained,  which  after  powdering  and  washing  consti- 
tutes one  of  the  varieties  of  the  pigments  obtained  from 
cobalt  and  known  as  Ceruleum.  There  are  other  ways 
of  obtaining  and  preparing  this  pigment.  One  of  these 
consists  in  precipitating  potassium  stannate  with  cobalt 
chloride,  collecting  and  washing  the  precipitate  and  then 
mixing  it  with  some  pure  silica.  Some  samples  contain 
calcium  sulphate  or  lead  sulphate  in  place  of  the  silica; 
these  are  of  an  inferior  quality. 

"  Ceruleum  is  a  permanent  pigment  of  a  rather  greenish 


154  MODERN  PIGMENTS 

blue  color  without  any  tendency  to  the  violet  cast,  so 
noticeable  with  other  cobalt  blues  when  viewed  by  gas 
or  candle  light.  It  suffers  little  or  no  change  by  exposure 
to  light  or  impure  air,  or  by  commixture  with  other  pig- 
ments. It  is  a  sub-opaque,  rather  earthy  pigment  with 
a  moderate  tinting  power." 

Although  some  painters  find  it  useful,  it  can  really 
become  so  only  when  used  where  such  deleterious  con- 
ditions exist  as  would  injure  the  otherwise  excel- 
lent imitations  that  can  be  made  of  it  from  mixing 
together  in  the  right  proportions,  viridian,  ultramarine 
blue,  and  zinc  white. 

It  is  never  offered  for  sale  in  America  except  as  an 
artist's  color  in  tubes,  and  is  likely  to  remain  so,  as  the 
general  trade  can  readily  dispense  with  it  and  without 
inconvenience. 

CHESSYLITE,  OR  BLUE  VERDITER 

Production,  Properties,   and   Uses 

Chessylite  comes  from  the  village  of  Chessy  near  the 
city  of  Lyons,  France,  or  rather  it  is  named  after  it.  It 
is  of  the  same  general  character  as  malachite,  and,  like 
that  pigment,  is  a  copper  compound,  but  contains  less 
hydrate  and  more  of  the  carbonate  of  that  metal.  It 
can  be  produced  artificially,  but  when  it  is  so  made  it  is 
not  as  permanent  as  the  natural. 

In  the  past  century,  and  especially  in  the  first  half,  it 
was  much  more  employed  than  it  is  now.  The  cobalt 
blues  and  their  ultramarine  imitations  have  well-nigh 
driven  it  out  of  the  market;  and  as  these  blues,  to  all 
intents  and  purposes,  are  non-poisonous  —  while  chessy- 
lite  is  not  —  there  can  be  no  good  excuse  for  continuing 
its  use.  It  should  be  abandoned. 


BLUE  PIGMENTS  155 

ROYAL  BLUE  —  BLUE  SMALT 

Properties    and    Uses 

Under  the  above  name,  glass  and  other  vitreous  sub- 
stances containing  cobalt  and  of  a  rich  blue  tone  have 
long  been  known. 

It  is  now  very  seldom,  if  ever,  used,  and  the  term  smalt 
has  itself  become  diverted  from  its  original  meaning,  and 
is  applied  to  coarsely  powdered  colored  glass  and  also  to 
coarsely  powdered  colored  sand  which  have  been  artifi- 
cially colored  not  only  in  blue  but  in  black,  or  anything 
else.  This  smalt  is  chiefly  used  to  sand  grounds  in  sign 
work,  the  grounds  having  first  been  painted  in  oil  color 
of  a  similar  tint  to  the  shade  of  the  smalt  thrown  over 
it  —  so  as  to  hold  the  latter. 

Formerly  blue  smalt  crystals  were  finely  powdered, 
washed,  and  the  lightest-weighted  particles  were  used  as 
pigment.  Owing  to  its  poor  covering  properties  and  the 
difficulty  in  using  it,  it  is  nearly  obsolete,  but  as  it  is 
indicative  of  the  origin  of  what  is  now  known  as  Smalt,  it 
is  well  worth  notice. 

There  are  several  other  blues  which  at  times  have  been 
used  as  pigments  either  in  oil  or  distemper.  All  of  them 
are  now  obsolete  and  their  place  taken  by  better  ones. 
The  introduction  of  artificial  ultramarine  blue  and  of 
Prussian  blue  has  nearly  destroyed  the  trade  in  other 
blues;  indigo  and  other  vegetable  blues  of  a  similar 
character  being  too  fugitive  and  unstable  in  strong  light, 
and  all  of  them  are  undesirable  in  many  respects. 


CHAPTER  XV 
BROWN  PIGMENTS.     UMBERS 

RAW  UMBER 
Provenance  and  Chemistry 

RAW  UMBER  is  an  earth  pigment,  and  is  found  in  every 
part  of  the  world.  As  may  be  supposed,  it  differs  greatly 
in  quality  as  well  as  in  composition,  and  its  variations  may 
well  be  called  numberless. 

The  umbers  which  have  been  found  and  mined  so  far  in 
America  are  very  inferior  in  quality  to  that  which  has 
come  to  be  regarded  as  the  standard  by  the  color  trade. 

The  umbers  mined  in  England  and  upon  the  continent 
of  Europe  come  closer  to  the  standard  of  excellence  than 
the  American  umbers  do;  still,  they  fall  short. 

That  which  is  found  in  the  island  of  Cyprus  possesses 
in  the  highest  degree  all  the  good  points,  consequently 
it  is  the  recognized  standard.  Some  few  samples  are 
mined  in  and  imported  from  Asia  Minor  that  are  little 
short  of  equaling  the  Cyprus  umbers,  and  at  one  time 
these  were  so  abundant  upon  the  market  that  umbers 
of  good  quality  were  named  after  them;  and  even 
to-day  in  the  United  States  all  good  umbers  are  sold  as 
Turkey  Umbers. 

Umbers  are  mined  like  all  earth  pigments  such  as  ochers, 
etc.,  and  in  their  natural  state  contain  impurities  which 
are  removed  by  levigations  in  the  manner  described  under 
ochers. 

166 


BROWN  PIGMENTS        .  157 

The  coloring  matter  of  umbers  is  due  to  both  iron  oxides 
and  to  manganese  dioxide.  To  the  latter  is  no  doubt  due 
its  excellent  drying  qualities  in  oil.  The  following 
analysis  by  Church  shows  the  composition  of  a  good 
sample  of  Cyprus  umber,  such  as  is  imported,  and  is 
fairly  representative  of  what  the  standard  of  excellence 
should  be: 

Water  given  off  at  100°  C 4.8 

Water  given  off  at  red  heat 8.8 

Iron  oxide  (Fe202) 48.5 

Manganese  oxide          19.0 

Lime       1.4 

Magnesia         0.5 

Phosphoric  acid  (P205) 2.1 

Silica 13.7 

Carbonic  acid,  etc 0.3 

100 

Properties  and  Uses 

The  color  of  a  good  raw  umber  should  be  a  greenish 
yellow  brown,  upon  the  citrine  order  when  dry.  It  is 
classed  among  the  semi-transparent  pigments.  It  can  be 
used  in  oil,  japan  varnish,  or  for  distemper  work,  and  in 
any  of  the  vehicles  gives  good  satisfaction.  Without 
doubt  it  is  the  most  useful  of  the  brown  pigments  to  be 
found  in  the  whole  list.  While  umber  is  not  so  brilliant 
as  the  burnt  siennas,  it  can  be  used  for  a  much  wider 
range  of  purposes,  and  it  is  a  pure  brown.  The  siennas, 
or  at  least  the  burnt,  should  have  been  classed  with  the 
reds,  but  the  raw  sienna  is  a  true  brown  and  this  saves 
a  double  classification  of  it. 

All  classes  of  painters  regard  umber  as  a  necessity: 
the  house  painter  to  mix  tints  from  it  for  his  drabs  and 
the  various  browns;  the  grainer  for  most  all  of  his  colors 
either  in  oil  or  in  distemper;  the  coach  and  car  painter 
for  mixing  many  popular  brown  tints;  the  kalsominer 


158  MODERN  PIGMENTS 

and  decorator  for  making  wall  tints;  the  frescoer  and 
decorators  for  mixing  into  tints  and  for  solid  work;  the 
japanner  for  the  hundreds  of  browns  and  drabs  of  which 
it  is  the  foundation;  and  the  artists  in  either  oil  or  water- 
colors.  What  would  they  do  without  it? 

It  is  prepared  by  paint  manufacturers  in  oil,  japan 
varnish,  and  in  distemper.  For  the  grinding  of  it  in  paste 
form  in  oil,  it  takes  up  nearly  as  much  linseed  oil  as  do 
the  siennas.  Next  to  these  also,  it  is  one  of  the  hardest 
of  the  earth  pigments  to  grind.  When  ground  in  oil  it 
should  be  clear-toned  without  any  muddiness,  and  when 
greatly  reduced  in  oil  should  not  show  any  specks  upon 
glass.  When  so  thinned  out  it  should  be  transparent. 
Quality  gives  umbers  their  chief  value;  the  strength  of 
coloring  matter  comes  only  second  to  that.  The  first  is 
an  easy  thing  to  determine  by  one  who  is  used  to  handling 
them.  To  test  for  quality,  it  should  be  spread  out  with 
the  palette  knife  and  smoothed  over  the  glass.  This  will 
enable  one  to  notice  the  clearness  of  tone,  its  richness  and 
the  fineness  of  grinding.  If  one  has  supplied  himself 
with  a  line  of  good  artists'  colors  in  tubes,  placing  a  trifle 
of  that  alongside  of  the  one  tested  there  will  be  no  trouble 
in  coming  to  a  right  conclusion  as  to  the  merits  of  the 
umber.  It  is  a  hard  matter  to  convey  by  words,  the  exact 
look  a  color  should  have,  therefore  the  advice  given 
under  directions  for  making  color  tests  —  of  providing  a 
full  line  of  good  artist  colors  to  judge  of  the  quality 
value  of  pigments  —  is  again  strongly  urged. 

The  scale  test  as  previously  described,  will  easily  detect 
any  undue  weakness  in  the  amount  of  coloring  matter 
contained,  and,  in  a  certain  measure,  the  tints  made  from 
them  will  help  in  forming  an  idea  of  the  quality  of  the 
umber.  As  to  the  strength  of  the  coloring,  one  should 
not  be  too  quick  in  condemning  the  weaker  simply 


BROWN  PIGMENTS  159 

because  it  may  not  be  as  strong  as  another.  Between 
two  umbers,  equal  in  other  respects,  the  better  of  the 
two  is  the  stronger;  but  between  two  samples  —  one 
of  which  is  greatly  superior  to  the  other  in  quality  — 
the  poorer  may  possibly  be  the  stronger.  In  such  a  case, 
no  mere  strength  can  atone  for  lack  of  quality.  Usu- 
ally, however,  the  better  the  quality  the  stronger  they 
are,  so  that  one  need  not  fear  the  making  of  a  test  for 
strength,  as  it  is  almost  a  sure  thing  that  the  best  toned 
will  be  also  the  strongest. 

The  better  class  of  manufacturers  are  now  putting  out 
their  pure  umbers  under  their  names  and  also  those  of 
dependable  quality  in  their  best  grade.  The  others  under 
their  names,  also  put  out  a  pure  umber,  but  sometimes  it 
is  not  of  the  best  quality,  and  in  reality  inferior  to  a  good 
one  that  is  adulterated.  At  the  risk  of  becoming  tedious 
in  repeating  it,  the  caution  is  again  given:  Purity  without 
quality  amounts  to  little  in  an  umber. 

Umbers  are  not  affected  injuriously  by  sunlight,  impure 
air,  nor  ordinary  heat.  By  constant  exposure  to  very 
high  temperatures,  it  becomes  more  reddish. 

The  raw  umbers  make  permanent  tints  of  great  beauty 
with  either  white  lead  or  zinc  white,  chiefly  of  the  drab 
order.  It  is  used  also  in  the  compounding  of  a  wide 
range  of  tints  with  other  colored  pigments,  and  for  the 
making  of  certain  neutral  greens  it  is  indispensable  to 
artists  and  decorators. 

.'  •  :      % 

BURNT  UMBER 

Properties  and  Uses 

It  is  needless  to  repeat  here  what  has  been  said  under 
the  heading  of  raw  umber,  as  very  much,  in  fact  nearly 
the  whole  of  it,  applies  with  equal  force  to  the  burnt. 


160  MODERN  PIGMENTS 

Aside  from  its  tone,  which  is  changed  to  a  deep,  rich 
brown,  all  the  rest  applies  to  it. 

As  the  name  indicates,  burnt  umber  is  a  calcined  umber. 
This  calcination  gives  its  rich  brown  color;  and  in  the 
better  grades,  it  will  be  of  a  clear  and  pure  tone  of  brown 
and  entirely  free  from  redness.  This  is  indeed  remarkable, 
and  must  be  a  peculiar  property  of  the  iron  oxide  con- 
tained in  the  best  grades  of  umber,  for  such  a  quantity 
of  iron  oxide  as  was  shown  in  the  above  analysis  of  raw 
umber  ought  to  make  it  of  a  decided  red  brown  after 
calcination,  and  the  poorer  sorts  do  show  it.  So  far  no 
satisfactory  explanations  have  been  given  which  account 
for  this  peculiarity.  In  the  American  and  other  inferior 
kinds  of  umber,  the  reddish  tone  shows  up,  and  that  is  a 
"dead  give-away"  as  to  their  provenance  and  quality; 
so  to  correct  it,  these  cheap  umbers  are  compounded  and 
manipulated  with  a  view  of  correcting  this  defect.  They 
are  mixed  with  some  of  the  semi-transparent  black  earths 
to  improve  the  tone  and  hide  the  reddishness  of  it  as  far 
as  possible.  While  the  compounding  kills  to  some  degree 
the  redness  of  the  umber,  it  does  not  entirely  do  so,  and 
the  addition  of  the  black  earths  renders  the  tone  muddy, 
and  there  is  no  clearness  in  them.  The  eye  in  most 
instances  is  sufficient  to  detect  the  imposition. 

Burnt  umber  is  used  for  all  kinds  of  painting,  and  for 
the  same  purposes  enumerated  under  the  heading  of  raw 
umber.  It  makes  a  different  order  of  tints  of  drabs  and 
browns  with  the  white  bases,  and  can  be  associated  with 
any  of  the  other  permanent  pigments  for  the  production 
of  an  innumerable  variety  of  tints.  Some  painters  have 
complained  of  the  tints  made  from  it  with  white  lead 
as  not  being  permanent.  All  pigments  which  contain 
oxide  of  iron  in  its  natural  state,  usually  have  it  in  an 
hydrate  form,  and  after  calcination  and  constant  exposure 


BROWN  PIGMENTS  161 

there  seems  to  be  a  slight  return  toward  the  natural 
condition  previous  to  calcination;  but  this  in  a  good 
umber  is  so  very  slight,  that  it  would  hardly  be 
noticeable.  The  probability  is  that  in  the  case  of 
many  of  these  complaints,  the  trouble  was  in  the 
sinking  of  the  oil  and  the  apparent  bleaching  out  of 
the  lead.  If  linseed  oil  is  applied  over  the  faded 
part,  the  color  will  be  restored  to  its  original  tint 
without  loss  of  intensity.  If  the  color  is  at  fault,  the 
applying  of  the  oil  will  not  restore  the  color,  if  that  is 
gone.  If  one  has  such  a  trouble,  it  will  be  an  easy 
matter  to  test  it,  and  to  ascertain  by  the  above  simple 
test  where  the  fault  lies. 

There  is  such  a  thing  as  false  economy;  and  that  it 
certainly  is,  to  buy  an  inferior  quality  of  burnt  umber. 
Much  of  the  disappointment  of  painters  in  its  use,  arises 
from  the  employment  of  poor  or  doctored  umbers. 

SIENNAS 

General  Characteristics    and   History 

Siennas  —  earths,  for  earth  they  are  —  are  really  a 
species  of  ochers  and  they  do  not  differ  greatly  from 
them  in  their  chief  constituents.  It  has  already  been 
explained  that  many  of  the  American  ochers  border 
upon  the  threshold  of  the  siennas,  and  on  this 
account  it  is  sometimes  very  difficult  to  place  them 
properly.  The  more  transparent  of  them  are  usually 
sold  as  siennas. 

Siennas,  then,  may  be  said  to  be  transparent  ocher  of  a 
brownish  yellow  tone.  The  finest  qualities  come  from 
Italy,  and,  as  their  name,  Terra  di  Sienna,  indicates,  are 
mined  near  the  city  of  Sienna.  But  it  is  found  else- 
where and  of  even  better  quality.  The  headquarters  for 


162  MODERN  PIGMENTS 

the  distribution  of  the  siennas  in  Italy  is  the  city  of 
Leghorn,  and  excellent  beds  of  it  are  found  in  the 
immediate  vicinity. 

Chemistry 

Siennas  usually  contain  a  larger  percentage  of  ferric- 
oxide  hydrate  than  do  most  of  the  European  ochers 
proper,  as  the  following  analysis  by  C.  H.  Hurst  indicates : 

Hygroscopic  water       .    .    .    .    .  8 . 2  to  17 . 5 

Combined  water       •.    .    .    .    .    .'  9.0  to  12. 4 

Manganese  dioxide  .    .    .    .    .    .  0 . 6  to    1.5 

Iron  oxide  (Fe2O3)       45.8  to  59.7 

Silica 5.0  to  17.4 

The  above  analysis  covers  the  extremes,  and  varia- 
tions will  be  found  between  the  two. 

Siennas  are  mined  as  other  ochers  are,  and  they  have 
to  be  purified  in  the  same  way  and  manner  as  was  fully 
indicated  under  that  heading. 

Properties  and  Uses 

It  is  an  easy  matter  to  judge  of  the  value  of  a 
sienna.  If  the  sample  to  be  examined  is  ground  in 
oil,  it  should  be  spread  upon  a  clean  piece  of  glass  in 
the  same  manner  as  for  the  umbers.  After  smoothing 
it  over  with  the  palette  knife,  one  can  judge  of  its 
clearness  of  tone  and  transparency  by  holding  it 
between  the  eye  and  the  light.  Spreading  with  a 
surplus  of  oil  will  indicate  the  fineness  of  the  grinding. 
If  it  has  been  properly  ground  it  will  be  entirely  free 
from  specks  or  cloudiness,  and  it  should  appear  com- 
pletely absorbed  by  the  oil.  In  the  raw  sienna,  the 
tone  should  be  a  clear,  subdued  yellow,  with  just  the 
slightest  tinge  of  brown  showing  in  it. 


BROWN  PIGMENTS  163 

RAW  SIENNA 

Properties  and  Uses 

Raw  sienna  is  useful  for  a  wide  range  of  work,  covering 
all  the  various  branches  of  painting. 

To  the  graining  trade  especially  it  is  most  indispensable; 
it  could  not  be  replaced  with  anything  else. 

The  general  house  painter  and  the  decorators  depend 
upon  it  for  the  making  of  many  beautiful  cream  tints 
in  linseed  oil,  with  the  usual  white  bases  or  with  whiting, 
etc.,  for  distemper  wall  work  or  decorations. 

Raw  siennas  are  absolutely  permanent.  No  change 
can  take  place  in  them  when  they  are  used  alone  and 
when  mixed  with  other  pigments;  the  only  changes  are 
such  as  take  place  in  the  pigments  with  which  they  are 
mixed  and  which  are  inherent  to  them,  and,  of  course,  such 
changes  as  are  natural  to  the  vehicles  used  in  their  appli- 
cation. 

BURNT  SIENNA 

Properties  and  Uses 

As  the  name  indicates,  this  is  the  raw  sienna  after  it 
has  been  calcined.  The  roasting  or  burning  produces  a 
very  great  change  in  the  color  of  the  raw  sienna.  It 
transforms  its  color  from  a  yellowish  brown  to  a  beautiful 
subdued  red-brown  of  great  richness.  So  rich  is  it, 
indeed,  in  some  of  the  better  samples,  as  to  create  the 
impression  in  the  beholder's  mind  that  possibly  it  might 
have  been  tampered  with,  and  had  been  "fixed  up"  and 
enriched  by  the  addition  of  a  lake.  Yet  in  all  the  best 
and  finest  qualities  of  that  pigment,  this  richness  is 
inherent  in  the  sienna  itself  and  this  tone  is 
permanent,  which  it  would  not  be  were  it  put  there  by 
laking  it  up. 


164  MODERN  PIGMENTS 

It  is  the  practice  of  some  color  makers  to  use  two  differ- 
ent kinds  of  burnt  siennas  in  their  grindings.  They 
choose  among  the  samples  of  native  siennas  such  as  are 
very  strong  in  coloring  matter,  and  these  they  grind  for 
the  general  trade,  who  use  siennas  mainly  in  the  making 
of  tints  with  white  lead  or  white  zinc  in  oil  or  with  whit- 
ing in  distemper.  A  word  must  be  put  in  here  regarding 
the  making  of  tints  with  burnt  siennas.  Even  the  very 
best  of  them  do  not  give  as  good  satisfaction  as  might 
be  expected  from  such  fine  pigments.  The  range  of  tints 
made  from  burnt  sienna  and  the  white  bases  are  at  best 
but  indifferent,  and  as  good  or  better  can  be  made  from 
the  use  of  Venetian  red  ocher  with  the  faint  addition 
of  black,  at  a  less  cost  for  material  and  with  equally  as 
good  results  as  far  as  durability  goes.  The  grinders,  being 
aware  of  this  peculiarity,  therefore,  use  an  indifferently- 
toned  burnt  sienna  which  is  strong  in  coloring  matter 
but  deficient  in  richness;  and  as  this  richness  is  only 
apparent  when  the  burnt  sienna  is  used  as  a  self  color,  it 
does  not  matter.  This  is  sometimes  labeled  as  House 
Painters'  Burnt  Sienna  to  distinguish  it  from  the  other 
grinding  which  they  make  of  the  rich  transparent  kind, 
and  which  is  labeled  by  them  as  Grainers'  Burnt  Sienna. 
This  is  intended  for  use  as  a  self  color,  and,  as  such,  all  the 
richness  is  appreciated  fully,  and  by  none  more  than  the 
grainers  and  decorators;  this  is  selected  for  the  very 
purpose  for  which  the  grainers  need  them,  transparency, 
richness  and  clearness,  associated  with  impalpably  fine 
grinding.  These  are  not  strong  as  a  rule,  and,  in  testing 
a  sienna  for  values,  the  mere  strength  should  never  be 
taken  into  consideration  in  estimating  the  higher  grades. 

Volumes  might  be  written,  but  all  would  not  be  said 
about  the  uses  and  abuses  of  the  siennas.  They  have 
many  friends  among  all  classes  of  painters  and  artists, 


BROWN  PIGMENTS  165 

and  the  few  who  have  any  trouble  with  them  will  find 
that  they  themselves  are  to  be  blamed  for  having  used 
them  for  purposes  and  under  circumstances  where  they 
should  not  have  been  employed. 

VAN  DYKE  BROWN 

Provenance  and   Preparation 

Van  Dyke  brown  is  a  pigment  of  bituminous  character, 
and  is  usually  found  in  or  near  bogs.  Many  theories  have 
been  advanced  as  to  what  it  really  is.  Some  suppose  it 
to  be  a  form  of  lignite,  resulting  from  the  decomposition 
of  vegetation.  However  that  may  be,  it  contains  more 
or  less  bitumen.  It  is  found  in  England  and  Ireland, 
but  the  best  that  is  upon  the  market  is  that  which  is 
imported  from  Cassel,  in  Germany. 

Vandyke  brown  is  known  as  cassel  earth  in  many  parts 
of  the  world.  It  contains  iron,  and  should  be  calcined 
and  well  cleaned  of  its  impurities  before  grinding. 

Properties   and    Uses 

Vandyke  brown  is  used  by  grainers  in  both  oil  and  in 
distemper,  and  by  some  in  the  coloring  of  fillers  for  fur- 
niture factories.  It  is  not  a  permanent  pigment,  and 
becomes  lighter  and  redder  by  exposure  to  sunlight.  It 
is  a  very  powerful  anti-drier  in  linseed  oil.  It  therefore 
requires  the  greatest  of  care  in  use.  In  tone  it  has  a 
peculiarly  pleasing  walnut  brown,  different  from  that  of 
any  other  pigment.  It  is  very  transparent,  and  that 
would  make  it  an  ideal  grainer's  pigment. 

But,  on  account  of  its  defects,  it  is  being  gradually 
replaced  by  burnt  umber,  tinged  to  imitate  its  tone  and 
to  correspond  so  nearly  to  it  as  to  deceive  the  casual 
observer. 


166  MODERN  PIGMENTS 

It  is  hardly  necessary  to  observe  that  tints  made  from 
it  with  the  whites  are  subject  to  fade  from  the  same 
causes  which  affect  the  color  when  it  is  used  by  itself, 
and  as  all  the  tints  which  can  be  made  from  it  are  readily 
reproduced  by  using  burnt  umber,  black  and  blue,  and 
that  when  they  are  so  made  they  are  permanent,  the  use 
of  Vandyke  brown  for  the  making  of  tints  has  nearly 
become  obsolete,  and  is  hardly  ever  resorted  to  except 
by  novices. 

The  grainers  will  hardly  be  willing  to  part  with  it  for 
distemper  work  in  the  graining  of  walnut.  It  is  better 
suited  to  that  than  any  other,  as  on  account  of  its  trans- 
parency there  is  a  depth  of  tone  shown  under  varnish, 
which  is  unattainable  by  the  use  of  any  brown  pigment. 

METALLIC  BROWNS 

Preparation  and  Manufacture 

Under  that  generic  appellation,  some  excellent  pig- 
ments are  produced  in  the  United  States.  All  are  native 
iron  ores  or  highly  ferruginous  earths  mined  in  all  parts 
of  the  country,  but  especially  in  the  Appalachian  system 
of  mountains  of  the  eastern  seaboard,  extending  from 
Pennsylvania  in  the  north  to  Alabama  in  the  south. 
The  Rocky  Mountain  system  contains  also  some  fine 
samples  of  these,  and  here  and  there  are  found  outcrops 
of  them  in  the  great  valley  between  the  two.  This  ore 
or  iron  earth  is  calcined  by  roasting,  pulverized,  levigated, 
dried  and  barreled,  and  is  then  ready  for  market.  There 
is  a  great  deal  of  variation  in  its  character  and  in  the 
amount  of  ferric-oxide  coloring  matter  it  contains. 

The  samples  vary  in  the  percentage  of  color  contained 
to  a  greater  degree  than  any  of  the  earth  colors,  ranging 
from  nearly  nothing  to  90  per  cent  of  iron  oxide.  The 


BROWN  PIGMENTS  167 

bases  upon  which  the  coloring  iron  oxide  rests  vary 
almost  as  much  as  that.  Most  of  these  browns  contain 
so  much  coloring  matter  that  the  color  itself  is  really  the 
base,  and  the  other  matter  found  with  it  is  of  so  small 
a  percentage  that  its  presence  is  merely  to  be  considered 
incidental. 

Properties  and  Uses 

The  metallic  browns  mix  readily  and  absorb  a  fair 
quantity  of  linseed  oil  as  a  rule,  the  nature  of  the  accom- 
panying base  having  something  to  do  with  that.  They 
range  in  tint  from  bright  red  brown  to  dark  purple, 
and  all  sorts  of  intermediate  shades  between  these 
extremes. 

Metallic  browns  are  extensively  used  for  roof  and  barn 
painting,  the  painting  of  iron  bridges,  structural  iron  and 
steel,  freight  cars,  etc.;  in  short,  for  nearly  everything 
where  a  good  substantial  covering  is  required,  where  the 
main  consideration  is  good  service,  but  does  not  lie  in 
the  beauty  of  the  finish. 

They  are  also  useful  in  the  making  of  certain  brown 
tints,  either  alone  or  as  adjuncts  to  other  pigments. 
The  manufacturers  of  mixed  paints  use  tons  in  their 
better  grades  either  as  bases  for  the  darker  tints  or  as 
tinting  colors  in  the  making  of  certain  shades. 

They  are  fairly  permanent,  showing  little  tendency 
to  change,  other  than  that  pertaining  to  all  iron  oxide 
pigments  —  that  of  darkening  by  age  —  but  linseed 
oil  probably  is  the  cause  of  as  much  of  it  as  the 
pigment.  No  one  should  hesitate  to  use  them  for 
all  kinds  of  work  where  a  cheap,  but  dependable  paint 
of  no  special  beauty  is  required.  They  can  be  much 
improved  in  looks  by  combining  with  some  of  the 
brighter  pigments. 


168  MODERN  PIGMENTS 

They  possess  great  covering  properties,  and  one  coat, 
even  when  thinned  excessively  with  linseed  oil,  will 
usually  cover  solid  any  other  color  over  which  it  is 
applied. 

It  commonly  comes  in  the  dry  state  packed  in  barrels 
of  300  pounds  capacity.  It  is  ground  in  oil  also,  and 
put  up  in  the  familiar  tin  packages  and  wooden  kegs  and 
barrels. 

SPANISH  BROWN 

Properties  and  Uses 

To  all  intents  and  purposes,  this  pigment  might  have 
been  included  with  the  mineral  browns.  As  a  distinctive 
appellation  to  designate  a  shade  of  brown  color,  it  has 
no  signification  whatever  to-day,  whatever  it  may  have 
had  in  that  regard  in  the  past.  It  is  still  known  and 
sold  under  that  name  in  many  localities,  but  this  is 
chiefly  confined  to  Pennsylvania,  Maryland,  and  the 
eastern  and  southern  seaboard.  Since  the  advent  of 
the  metallic  browns,  the  name  has  become  a  memory 
with  the  older  painters  of  the  middle  and  western  states, 
and  is  almost  unknown  to  the  younger  generation  of  the 
craft. 

All  that  can  be  said  for  it  is  that  under  the  name,  any- 
thing, or  rather  any  kind  of  a  dirty  red  brown  earth,  is 
usually  sold  as  such,  and  the  grades  of  metallic  browns, 
which  are  sometimes  sold  as  Spanish  Brown,  are  of  a 
lower  order  than  are  those  sold  under  other  names. 

The  use  of  the  name  should  be  discouraged  as  it  is  not 
best  to  have  confusing  elements.  The  nomenclature  of 
pigments  is  complex  enough  to  suit  the  most  fastidious, 
and  the  purpose  should  be  to  keep  it  as  simple  as  possible. 

Other  substances  have  been  and  are  listed  as  brown 
pigments  by  certain  houses  catering  to  the  artist's  trade. 


BROWN  PIGMENTS  169 

None  of  these  have  any  special  virtues  worth  noticing 
here  and  they  are  passed  by.  Most  of  them  are  but 
variations  of  some  of  those  that  are  listed  and  described — 
such  as  bister  and  asphaltum  —  and  are  so  undesirable, 
even  for  artists'  use,  that  they,  as  well  as  the  painters  and 
decorators,  might  profitably  learn  to  dispense  with  them 
as  pigments,  whatever  value  they  may  have  in  other 
respects. 


CHAPTER  XVI 

BLACK  PIGMENTS 

LAMP  BLACK 

Chemistry  and  Manufacture 

THERE  cannot  possibly  be  any  hesitation  or  uncertainty 
experienced  in  selecting  a  black  for  first  place  on  the 
list.  This  place  belongs  by  common  consent  to  lamp 
black.  Although  it  is  far  from  being  the  blackest  black, 
or  the  purest  toned  black,  it  must  be  accorded  first 
place,  because  of  its  greater  usefulness  over  any  of  the 
other  blacks. 

Lamp  black  is  a  soot,  produced  by  the  incomplete 
combustion  of  resins,  resinous  woods,  fats  and  fatty  oils, 
paraffin  and  paraffin  oils.  These  substances  are  burned 
with  an  insufficient  supply  of  air,  so  that  a  considerable 
portion  of  the  carbon  they  contain  may  be  deposited  as 
soot.  The  soot  thus  produced  is  far  from  being  pure 
carbon,  and,  of  necessity,  much  of  the  tarry  products  of 
imperfect  production  or  destructive  distillation  are  present 
in  combination  with  it.  These  foreign  admixtures  give 
it  the  undesirable  tones  to  be  found  in  the  inferior  grades. 
Owing  to  their  greasiness  it  is  almost  impossible  to  use 
them  with  linseed  oil,  as  they  are  highly  non-drying. 
Much  of  the  impurity  is  deposited  in  or  near  the  first 
receiving  chamber,  and  the  lamp  black  which  is  deposited 
the  farthest  away  from  where  the  substances  are  burned 
is  the  freest  from  impurities. 

170 


BLACK  PIGMENTS  171 

Calcination  in  an  intense  red  heat  burns  up  most  of 
these  non-drying  oils  and  tarry  products  and  then  the 
lamp  black  is  perfect.  The  first  that  is  deposited  is 
usually  sold  dry  in  the  well-known  small  paper  cones, 
and  these  bear  no  manufacturers'  names.  The  rest  is 
selected  and  graded  according  to  its  color  and  freedom 
of  foreign  matter.  Usually  there  are  three  qualities 
selected  besides  the  inferior  one  mentioned. 

Some  substances  produce  a  better  lamp  black  than 
others,  and  there  are  many  little  tricks  of  trade  and 
manipulations  known  to  and  employed  by  certain  manu- 
facturers that  are  probably  not  known  to  others,  as  some 
do  produce  much  better  blacks  from  the  same  material. 

Properties  and  Uses 

Lamp  black  being  nearly  pure  carbon  is  inalterable 
and  is  absolutely  permanent  and  unchangeable. 

The  oft-cited  signboard  left  and  forgotten  for  genera- 
tions in  the  back  yard,  and  which  has  had  its  ground 
coats  of  white  paint  eaten  away,  and  where  the  board 
itself  is  disappearing  in  the  shape  of  lint  picked  up  by 
birds,  for  the  making  of  their  nests,  until  the  black  letter- 
ing painted  upon  it  originally,  stands  out  as  if  carved 
out  from  the  wood,  in  bold  relief  among  the  general 
decadence  surrounding  it,  is  a  very  good  illustration  of 
its  permanency  and  preserving  powers.  Such  old-time 
signboards  may  be  found  and  noticed  in  any  neighbor- 
hood. 

Lamp  black  seems  to  act  as  a  preservative  from  decay 
to  the  linseed  oil  and  to  help  it  postpone  indefinitely  the 
day  when  it  should  go  the  way  of  all  flesh  and  perish. 

One  of  the  chief  uses  of  lamp  black  is  in  the  making 
of  gray  tints  with  white  lead  and  zinc  white,  as  the  tints 
so  made  are  free  from  the  brown  gray  tones  so  objection- 


172  MODERN  PIGMENTS 

able  in  some  of  the  bone  blacks,  and  especially  of  the  red 
brown  grays  produced  by  the  use  of  gas  or  carbon  blacks. 
The  lamp  blacks  give  a  clear-toned  clean  bluish  gray,  or 
rather  the  cast  of  it,  as  it  is  not  a  blue  tone  at  all.  These 
grays  are  distinctively  its  property,  and  through  them 
may  be  distinguished  its  purity  and  quality.  Lamp 
black  is  very  strong  in  coloring  matter,  and  its  strength 
makes  it  an  economical  tinting  agent. 

For  solid  painting,  where  an  intense  black  is  required, 
it  may  not  be  as  good  as  some  of  the  bone  blacks,  but 
when  any  solid  black  painting  is  done,  where  intensity  of 
tone  is  not  of  the  first  importance,  its  use  will  prove  much 
the  most  satisfactory. 

On  account  of  the  lightness  of  its  weight  and  conse- 
quent bulkiness,  it  is  very  difficult  to  mix  it  with  water. 
It  floats,  and  no  amount  of  ducking  it  under  will  make 
it  stay  down.  When  it  is  wanted  for  use  in  distemper, 
it  should  first  be  mixed  to  a  stiff  paste  with  vinegar,  in 
which  liquid  it  is  not  so  refractory  as  it  is  in  water.  It 
can  afterwards  be  thinned  with  glue  water  and  used  for 
the  making  of  tints  or  by  itself  as  desired. 

From  its  great  bulk  it  may  be  well  surmised  that  it 
absorbs  great  quantities  of  linseed  oil,  and  it  surely  does. 
In  fact,  it  absorbs  more  than  any  of  the  other  pigments. 
Owing  to  the  great  quantity  of  oil  it  absorbs,  many 
grinders  cannot  resist  the  temptation  to  add  some 
barytes  to  it.  This  can  be  done  without  the  use  of  any 
additional  oil,  but  this  can  be  detected  readily  by  the 
smaller-sized  packages  required  to  pack  any  given  weight 
of  it.  The  smarter  ones  put  some  bulky  stuff  along  with 
it,  and  then  the  eye  will  not  suffice,  and  a  scale  test  will 
be  required  to  determine  its  purity.  There  should  be 
but  very  little  difference  between  two  samples  of  equal 
purity,  as  to  their  strength.  However,  one  may  have 


BLACK  PIGMENTS  173 

been  ground  with  more  oil  than  another,  or  have  lain 
upon  the  shelves  until  the  oil  has  risen;  therefore  the 
samples  should  be  placed  upon  a  piece  of  blotting  paper 
and  the  oil  extracted  from  them  so  all  may  be  used  in 
the  same  form  of  a  very  stiff  paste  before  weighing  them. 
A  good  lamp  black,  even  the  very  best,  is  never  of  a  jet 
tone,  and  alongside  of  a  good  bone  black  it  looks  grayish 
black.  Therefore,  if  it  looks  blacker  than  it  should  to 
a  person  in  the  habit  of  using  lamp  black,  it  is  possible 
and  nearly  certain  that  it  has  been  bolstered  up  with  an 
admixture  of  gas  black. 

It  is,  or  rather  has  been,  the  habit  of  some  grinders 
of  small  reputation  as  to  the  class  of  colors  they  put  out, 
to  use  a  cheap  or  poor  lamp  black  and  to  color  it  up  with 
carbon  black,  so  that  it  will  pass  muster.  If  this  is  sus- 
pected, it  can  be  quickly  determined  by  simply  using  a 
little  with  some  white  lead  which  should  make  a  gray  tint 
of  it.  If  it  produces  the  usual  gray  without  any  brownish 
hue  to  it,  the  lamp  black  is  all  right;  if,  however,  the  tint 
so  made  does  show  a  brownish  tone,  a  solemn  oath  can 
be  taken,  without  fear  of  perjuring  one's  self,  that 
the  black  has  been  tampered  with  and  that  the  tam- 
pering agent  is  gas  or  carbon  black.  Any  court  would 
clear  one  of  perjury  after  reading  the  evidence  presented 
by  a  chemical  analysis  and  the  sworn  statements  of 
its  examination  by  experts. 

GAS  OR  CARBON  BLACK 
Properties  and    Uses 

Gas  or  Carbon  black,  as  it  is  indifferently  called,  is 
really  only  a  variety  of  lamp  black.  It  is  produced  in  a 
similar  manner  as  that  pigment,  but  with  this  difference, 
that  it  is  made  exclusively  from  the  incomplete  combus- 


174  MODERN  PIGMENTS 

tion  of  natural  gas.  It  is  therefore  the  soot  produced 
by  that  commodity. 

It  is  readily  distinguishable  from  true  lamp  black  in 
that  it  is  by  far  the  blacker  looking  black  of  the  two,  and 
that  for  jettiness,  true  lamp  black  alongside  of  it  —  is 
not  in  it. 

While  the  tone  of  this  black  is  very  superior  to 
lamp  black,  it  possesses  some  very  grave  defects  that 
have  in  a  great  measure  prevented  its  adoption  for 
general  use.  Should  these  defects  ever  be  satisfactorily 
overcome,  it  then  would  become  the  black,  for  solid 
painting  at  least. 

One  of  its  principal  faults  is  that  when  mixed  with 
linseed  oil,  it  livers  it.  In  trade  parlance,  liver  ing  means 
that  peculiar  action  some  pigments  have  of  turning  the 
oil  into  a  jelly-like  condition;  it  thickens  to  such  an 
extent  that  it  cannot  be  used  with  the  brush  in  painting. 

The  livering  of  gas  black  is  prevented  to  a  certain  extent 
by  compounding  it  with  other  pigments,  and  the  best  use 
that  is  made  of  carbon  black  is  when  it  is  associated  with 
other  blacks.  The  sign  writer's  so-called  blacks  are 
usually  compounded  from  true  lamp  black  and  carbon 
blacks. 

Its  one  other  great  fault  has  been  noted  already.  It 
makes  very  poor  grays,  and,  while  a  true  lamp  black  can 
be  improved  with  it  in  self  color  for  solid  black  painting, 
yet  on  account  of  its  poorness  for  tints  it  must  be  con- 
sidered as  an  adulterant,  as  the  innocent  purchaser 
might  want  it  for  the  making  of  tints,  and  in  that  case  he 
is  simply  swindled.  Why  not  sell  each  for  what  it  is 
and  let  the  painters  do  their  own  compounding?  In  the 
case  of  a  sign-writer's  black,  it  is  different.  Then  it  is 
not  passed  as  a  lamp  black  or  any  particular  black,  and 
the  name  itself  indicates  that  it  is  to  be  used  for  solid 


BLACK  PIGMENTS  175 

painting.  If  one  uses  it  for  making  tints,  he  does  so  at 
his  own  risk,  because  the  label  does  not  convey  any  idea 
of  its  fitness  for  it. 

Some  manufacturers  have  put  out  carbon  blacks  under 
various  names,  but,  for  probably  good  reasons,  none  of 
them  have  become  very  popular  so  far;  and  while  they 
seem  to  have  stopped  the  livering  of  it,  this  may  have 
been  done  at  the  expense  of  another  quality  of  the  pig- 
ment which  has  been  disturbed  by  the  addition  of  the 
preventive.  Be  that  as  it  may,  it  certainly  is  a  fine- 
looking  black,  and  it  is  a  pity  that  it  does  not  possess  the 
other  good  qualities  of  lamp  black;  if  it  did  —  that  would 
not  be  in  it. 

Its  best  use  has  been  upon  ship  work.  Steamships 
painted  with  it  look  immensely  better  than  when  painted 
with  ordinary  lamp  black.  Nearly  all  the  transatlantic 
lines  now  use  it  regularly  for  that  purpose. 

IVORY  BLACK  —  DROP  BLACK  —  COACH  BLACK 

Manufacture  and  Preparation 

Ivory  black,  drop  black  and  coach  black  form  a  trinity  of 
blacks,  but  in  reality  are  but  one  and  the  same  black,  with 
the  exception  hereafter  named.  So  it  is  thought  best  to 
bunch  them  under  one  head. 

The  above  blacks  are  all  bone  black.  The  bone  black 
selected  for  their  manufacture  should  be  from  the  hardest 
and  jettiest  samples. 

Bone  black  would  be  too  common  a  name  for  these 
blacks,  and  probably  for  that  reason  it  has  been  dubbed 
ivory  black.  It  stands  to  reason  that  as  there  is  scarcely 
enough  ivory  in  existence  to  supply  the  demand  for  ivory 
black  in  the  United  States  alone  for  a  single  year,  let 
alone  the  demands  that  exist  for  it  in  Europe  and  all 


176  MODERN  PIGMENTS 

civilized  countries,  the  black  that  is  sold  under  that 
name  cannot  be  it. 

Bone  black  is  properly  animal  charcoal.  This  is  made 
upon  the  same  principle  as  wood  charcoal.  The  bones 
are  placed  in  a  retort  and  are  calcined  in  a  hot  furnace 
where  atmospheric  air  is  excluded.  The  better  qualities 
of  bone  black  are  made  from  selected  hard  bones  such  as 
animals'  teeth,  etc.  The  resulting  bone  charcoal  is  pul- 
verized before  placing  upon  the  market. 

The  variety  of  it  known  as  drop  black  is  the  same  black 
made  into  little  cones  of  the  shape  and  size  of  a  large 
chocolate  drop  —  in  which  form  it  was  more  familiar 
to  old-time  painters  than  to  those  of  the  present  day. 
These  little  cones  resulted  from  the  bone  black,  which, 
after  grinding,  had  been  mixed  with  water  (holding  a  slight 
adhesive  in  solution)  into  a  stiff  paste,  and  the  little  dabs 
of  it  placed  upon  trays  to  dry  were  the  cones  or  drops 
which  gave  the  bone  black  the  name  it  still  carries  to-day 
—  minus  the  drops.  The  drops  were  placed  upon  a 
marble  slab  and  ground  with  oil  with  a  muller  after  first 
crushing  it.  That  made  life  a  burden,  or  at  least  the 
painters  of  that  period  thought  so,  for,  if  they  had  a  large 
job  upon  which  it  had  to  be  used,  it  meant  the  spending 
of  their  evenings  till  ten  or  eleven  o'clock  grinding  away 
for  dear  life. 

Ivory  and  drop  black  have  a  small  admixture  of 
Prussian  blue  added  to  them  to  correct  any  brownish 
tone.  Coach  black  has  no  blue  added  to  its  bone  black 
composition.  That  is  all  the  difference  that  there  is 
between  them.  A  color  manufacturer,  to  whom  the 
writer  had  once  made  the  same  criticism,  laughingly 
replied  that  there  was  still  another  difference  which  had 
been  forgotten,  and  when  asked  what  this  was  replied, 
" 'The  different  labels  upon  the  cans." 


BLACK  PIGMENTS  177 

The  ivory  blacks  are  used  in  oil,  japan,  varnish  and 
water.  They  are  good  blacks  when  well  made  and  are 
used  in  all  mediums.  As  an  oil  color  they  are  usually 
too  transparent  to  use  for  solid  painting,  except  as  a  last 
coat  over  a  previous  solid  one  of  lamp  black,  where  that 
color  is  insufficiently  black  to  suit.  They  are  excellent 
in  distemper,  and  the  grainers  find  them  advantageous 
for  their  work  in  either  distemper  or  oil,  for  the 
working  in  of  dark  veins,  knots  or  shades,  for  which 
they  are  admirably  adapted  on  account  of  their  trans- 
parency. 

In  japan  they  are  invaluable  to  the  car  and  carriage 
painters.  The  carriage  manufacturers  use  enormous 
quantities  of  it  in  the  painting  of  buggies,  surreys,  coaches, 
etc.,  not  only  for  the  solid  black  painting,  but  for  the 
mixing  of  the  numberless  dark  greens  used  by  the  trade 
in  the  painting  of  everything  that  runs  on  wheels. 

Formerly  every  carriage  shop  used  to  buy  the  various 
colors  ground  separately  and  mix  the  various  shades  in  the 
shop  as  wanted,  but  now  few  of  them  do  so,  and  these 
various  dark  greens  under  an  array  of  magnificent  names 
are  compounded  and  made  to  match  at  color  works  where 
the  proper  facilities  exist  for  handling  them  to  the  best 
advantage  and  with  the  most  assurance  of  duplicating 
them  semper  idem.  The  multitude  of  names  given 
special  blacks,  or  rather  grindings  of  them,  is  bewildering, 
as  every  manufacturer  has  a  long  list  of  his  own  which 
he  tries  to  make  as  puzzling  as  he  can,  and  besides 
that  he  has  a  number  of  special-formula  blacks  which  he 
grinds  for  certain  carriage  factories,  each  having  a  special 
name.  One  may  as  well  look  for  a  needle  in  a  haystack  as 
to  try  to  understand  the  average  coach  color  list.  About 
the  only  indication  of  quality  is  the  net  price,  and  fre- 
quently even  that  —  is  not. 


178  MODERN  PIGMENTS 

All  this  confusion  about  an  article  which,  when  let 
alone,  is  purely  bone  black,  looks  to  the  disinterested 
spectator  as  if  there  might  be  some  money  in  it,  or  it 
could  not  be  kept  up.  If  goods  were  simply  labeled  and 
sold  for  what  they  were,  as  first,  second,  third,  or  fourth 
quality,  or  as  compounds  of  this  and  that,  then  it  would 
be  easy  for  one  to  know  what  he  was  buying;  while,  if  the 
average  buyer  can  be  puzzled,  there  exists  a  chance  to 
demand  an  undue  profit. 

The  ivory  blacks  are  also  used  largely  by  the 
japanning  plants,  enameling  works  of  all  kinds,  bicycle 
factories,  etc.,  they  are  very  permanent  under  any  and 
all  situations. 

CHARCOAL  BLACK,  OR  BLUE  BLACK 

Preparation,  Properties',  and  Uses 

As  the  name  of  this  pigment  indicates,  or  at  least  one  of 
the  two  names  under  which  it  is  known  in  the  United 
States  does  give  an  inkling  of  its  origin.  Charcoal  black 
is  a  product  due  to  combustion,  and,  like  ivory  black,  it  is 
also  a  charcoal,  but  there  is  no  bone  or  any  sort  of 
animal  matter  in  its  composition.  It  is  a  wood  charcoal 
and  of  vegetable  origin. 

The  wood  used  in  the  making  of  it  has  a  great  deal  to  do 
with  its  quality.  This  wood  should  be  entirely  free  from 
resinous  matter.  Some  of  the  best  of  it  is  produced  by  the 
calcination  in  a  close  vessel  at  a  high  heat  of  peach  and 
plum  pits,  cocoanut  shells,  cork  waste,  grape-vine  cuttings, 
etc.,  the  powdered  charcoal  of  which  forms  the  blue  black 
of  commerce. 

It  is,  of  course,  essential  in  a  good  black  that  the  cal- 
cination should  be  thoroughly  done,  so  that  the  product 
may  be  free  from  any  tarry  or  empyreumatic  substances. 


BLACK  PIGMENTS  179 

Blue  black  is  unchangeable  and  entirely  reliable  in  dis- 
temper work,  and  for  that  purpose  is  the  black  par  ex- 
cellence. Decorators  arid  artists  use  it  mostly,  and  that 
only  in  water  colors.  It  is  also  used  occasionally  by  some 
grainers. 

In  oil  it  has  little  if  any  body,  and  for  that  reason  is 
seldom,  if  ever,  used  but  as  a  glazing  color,  or  for  shading, 
and  obtaining  certain  effects  of  depth  unattainable  with 
body  pigments. 

GRAPHITE,  BLACK  LEAD,  OR  PLUMBAGO 

Production  and  Preparation 

Graphite  is  the  name  under  which  this  substance  is  best 
known  as  a  pigment  in  the  United  States,  and  is  a  mineral 
carbon  of  a  peculiar  atomic  formation.  It  is  found  in  all 
parts  of  the  known  world  with  considerable  difference  in 
its  quality,  sometimes  varying  a  good  deal  in  the  same 
ledge  or  vein. 

That  found  in  the  Ural  Mountains  in  Russia  is  the  best 
of  any  mined  in  the  Old  World.  Mexico  produces  the 
best  that  has  been  found  so  far  in  the  New  World.  There 
is  much  of  it  mined  in  the  United  States,  especially  in 
New  England,  and  it  exists  in  New  York  State  in  the  Lake 
Champlain  region.  It  is  seldom  found  in  a  state  of  entire 
purity,  and  calcination  is  the  means  usually  employed  to 
free  it  from  impurities.  The  ashes  of  these  are  removed 
by  levigation.  After  repeated  washings,  it  should  be 
digested  with  a  strong  solution  of  hydrochloric  acid  to 
remove  any  iron  or  alumina.  After  another  levigating 
it  is  washed  in  a  leaden  vessel  with  hydrofluoric  acid  to 
remove  the  silica.  After  another  thorough  washing 
and  grinding  to  reduce  it  to  a  fine  powder,  it  is  ready 
for  use. 


180  MODERN  PIGMENTS 

For  distemper  work  it  can  be  relied  upon  never  to 
change.  It  is  also  permanent  in  oil,  and  when  ground  in 
that  media  it  is  of  a  dark  slate  color.  It  is  an  excellent  iron 
paint,  and  is  now  extensively  used  for  that  purpose  and  as 
a  paint  for  tin  roofs.  The  dullness  of  its  color  is  against 
it  for  anything  but  utilitarian  purposes. 

One  great  fault  with  it  is  that  it  shows  markings  readily, 
and  a  surface  painted  with  it  soon  resembles  a  huge  slate 
upon  which  everything  that  touches  it  with  a  little  force, 
leaves  its  mark;  unfortunately,  unlike  a  slate,  it  cannot 
be  sponged  off. 

There  are  a  number  of  other  black  and  semi-black 
pigments  that  might  be  added  to  the  above  list,  but  they 
are  mostly  obsolete,  or  of  such  a  nature  that  they  do  not 
deserve  notice.  For  instance,  certain  black  or  semi- 
black  natural  earths  sometimes  listed  in  catalogues  as 
Mineral  Blacks  have  never  had  any  standing,  nor  have 
they  ever  received  the  recognition  of  the  paint  trade. 
They  have  mainly  served  the  purpose  of  swelling  the 
lists  of  a  few  paint  grinders  who  may  possibly  have  local 
trade  in  them  for  special  purposes  to  which  they  may  be 
adapted  or  used  through  ignorance  of  better. 

Such  blacks  as  India  ink,  which  are  principally  special 
preparations  of  lamp  black,  do  not  come  within  the  scope 
of  this  treatise. 

The  above  comprises  all  the  useful  pigments.  There 
are  many  compounds  that  are  palmed  off  upon  the  public 
as  pigments  which  will  be  vainly  looked  for  here.  Such 
have  no  more  legitimate  right  to  the  name  than  would 
have  any  others  of  the  thousands  of  tints  made  by  the 
combination  of  true  pigments.  For  instance,  the  stuff 
sold  under  the  name  of  Gray  Ocher,  is  not  an  ocher  at  all, 
and  is  a  poor  compound  of  shale  or  soft,  crushed  stone. 


CHAPTER  XVII 
A  TABLE  OF  SYNONYMS 

No  little  confusion  exists  in  the  minds  of  many  men, 
as  to  what  is  the  right  or  proper  name  for  certain  pigments. 
When  they  happen  to  know  a  pigment  by  a  given  name, 
and  it  happens  that  this  pigment  is  offered  them  by  a 
dealer  or  is  listed  in  a  catalogue  under  another  title,  they 
are  deterred  from  using  it,  as  they  cannot  recognize  it 
under  its  other  name,  and  they  suppose  it  to  be  entirely 
different  from  the  one  they  want. 

It  is  deplorable  that  there  is  no  universally  acknowl- 
edged nomenclature  for  pigments  that  would  be  recog- 
nized in  all  languages  all  over  the  world,  or  even  an 
acknowledged  nomenclature  for  the  English  speaking 
nations. 

Custom  in  the  United  States  is  beginning  to  fix  definite 
meanings  to  certain  designations,  whereby  a  few  of  the 
pigments  and  their  different,  qualities  may  be  known,  but 
the  work  is  far  from  complete  and  from  being  universally 
acknowledged  even  by  our  nation  alone.  So  in  Canada, 
Australia,  New  Zealand,  the  British  Isles,  where  trade 
connections  are  not  very  close  with  us,  the  variations 
are  bound  to  be  greater  than  the  ones  which  exist  here 
where  the  usages  of  the  paint  trade  have  established  a 
quasi-uniformity  in  a  few  of  the  leading  pigments  at 
least. 

The  names  which  have  been  adopted  in  this  treatise 
and  which  have  been  given  to  the  various  pigments,  are 

181 


182  MODERN  PIGMENTS 

those  under  which  they  are  principally  known  and  sold 
in  the  United  States. 

In  the  following  tables  the  name  adopted  as  standard 
in  the  preceding  chapters  for  each  pigment  will  be  given 
preference.  It  will  be  placed  in  the  left  column.  The 
synonyms  under  which  the  pigment  is  also  known  will  be 
found  in  the  column  upon  the  right,  and  all  bracketed 
together  when  more  than  one  is  used. 

Thus  any  one  seeking  information  concerning  a  pig- 
ment which  he  knows  under  another  name  than  that 
which  is  given  it  in  the  treatise,  can  readily  find  it  by 
looking  for  it  in  the  right  column  of  the  group  of  colors 
to  which  it  belongs,  then,  having  found  it,  look  at  the  left 
column,  where  he  will  find  the  name  adopted  for  that 
same  color,  under  which  name  he  will  find  the  des- 
cription he  seeks. 

To  facilitate  the  finding  of  the  names,  the  same  classi- 
fication and  grouping  have  been  followed  as  in  the  descrip- 
tion given  the  pigments.  This  renders  the  finding  of  any 
certain  color's  names  an  easy  task. 

TABLE  OF  SYNONYMS 

The  White  Pigments 


White  lead 


Flake  white. 
Cremnitz  white. 
Silver  white,  or 

Blanc  d'argent. 
Cerusa  or  ceruse. 
Cremser  weiss  (Ger.). 
Blanc  de  plomb  (Fr.). 
f  Chinese  white. 


Zinc  white 

Blanc  de  zinc  (Fr.). 

{Carbonate  of  lime. 
Spanish  white. 
Paris  white. 


TABLE  OF  SYNONYMS 


183 


Kaolin     .    .    . 
Gypsum       .    . 

White  silicate 


Baryta  white 


China  clay. 
Sulphate  of  lime. 
Silver  white. 
Powdered  silica. 
Barytes. 

Sulphate  of  barium. 
Floated  barytes. 
Heavy  spar. 
Permanent  white. 
Permanent  weiss  (Ger.). 
Blanc  fixe  (Fr.). 


The  Yellow  Pigments 


Ocher 


Chrome  yellow 


Baryta  lemon  yellow 


Gamboge 
Aureolin 


Indian  yellow 


Yellow  ocher. 
French  ocher. 
Roman  ocher. 
Mineral  yellow. 
Brown  ocher. 
American  ocher. 
Oxford  ocher. 
Mars  yellow. 
Mars  orange. 
Artificial  ocher. 
Gelben  ocher  (Ger.). 
Mars  gelb  (Ger.). 
Ochre  jaune  (Fr.). 
Jaune  de  Mars  (Fr.). 

Chrome. 

Chromate  of  lead. 
Canary  chrome  yellow. 
Lemon  chrome  yellow. 
Orange  chrome  yellow. 
Crom  gelb  (Ger.). 
Chrome  jaune  (Fr.). 

Baryta  yellow. 

Barium  chromate. 

Yellow  ultramarine. 

Permanent  yellow. 

Gomme  gutte. 
[Cobalt  yellow. 
{Kobalt  gelb  (Ger.). 
I  Jaune  de  cobalt  (Fr.). 
rPiuri. 

Puree. 
jPeori. 

Indisch  gelb  (Ger.) 
Uaune  Indien  (Fr.). 


184 


MODERN  PIGMENTS 


Naples  yellow 


Dutch  pink 


King's  yellow 


Cadmium  yellow 


Giallo  di  Napoli  (It.). 
Neapel  gelb  (Ger.). 
Jaune  de  Naples  (Fr.). 
Jaune  d'antimoine  (Fr.). 

Yellow  lake. 
Brown  pink. 
Citrine  lake. 
Yellow  madder. 
Italian  pink. 
Quercitron  lake. 
Dunkel  gelb  lack  (Ger.). 
Laque  brun  jaune  (Fr.). 

Orpiment. 
Konigs  gelb  (Ger.). 
Jaune  royal  (Fr.). 

Orient  yellow. 
Aurora  yellow. 
Orange  cadmium. 
Sulphide  of  cadmium. 
Cadmium  gelb  (Ger.). 
Jaune  de  cadmium  (Fr.). 
Jaune  brilliant  (Fr.). 


The  Red  Pigments 


Vermilion 


Vermilions  Reds  or  Imitation 
Vermilions , 

American  vermilion 


Venetian  red 


Indian  red 


Cinnabar. 
English  vermilion. 
Chinese  vermilion. 
Zunsober  (Ger.). 
Vermilion  (Fr.). 

Sold   under  a  multitude   of  pro- 
prietary names. 
Chromate  of  lead. 

Rouge. 

Crocus. 

Colcothar. 

Caput  mortuum  vitrioli. 

Burnt  ocher. 

Sinoper  (Ger.). 

Rouge  de  Venise  (Fr.), 

Ochre  rouge  (Fr.). 

Persian  red. 
Indian  red  ocher. 
Indische  roth  (Ger.). 
Rouge  d'Inde  (Fr.). 


TABLE  OF  SYNONYMS 


185 


Madder  lakes 


Indian  lake 


Carmine 


Red  ocher 


Red  lead 


Pink  madder  lake. 
Rose  madder  lake. 
Madder  carmine. 
Madder  red. 
Rubens  madder. 
Madder  purple. 
Madder  lake. 
Madder  brown. 
Krapp  lack  (Ger.). 
Carmm  de  Garance  (Fr.) 
Laque  de  Garance  (Fr.). 

Lac  lake. 

Lack  lack  (Ger.). 

Laque  d'Inde  (Fr.). 

rimson  lake. 
Purple  lake. 
Carmin  lack  (Ger.). 
"armin  (Fr.) 
Laque  Cramoisi  (Fr.). 

Red  hematite. 
Red  iron  ore. 
Scarlet  ocher. 
Red  chalk. 
Ruddle. 
Terra  rosa. 
Miltos. 
Rubrica. 
Sinopis. 
Sinoper. 

Ochre  roth  (Ger.). 
Ochre  rouge  (Fr.). 
f  Minium 
l-Monium  rubrum 


The  Green  Pigments 


Chrome  yellow 


Cobalt  green 


Extra  light  chrome  green. 
Light  chrome  green. 
Medium  chrome  green. 
Dark  chrome  green, 

and  a  host  of  proprietary  names. 

Zinc  green. 
Rinkman's  green. 
Kobalt  grim  (Ger.). 
Vert  de  cobalt  (Fr.). 
Vert  de  zinc  (Fr.). 


186 


MODERN  PIGMENTS 


Viridian 


Terre  verte 


Green  oxide  of  chromium    . 


Malachite 


Paris  green 


Scheele's  green 


Verdigris 


Emerald  oxide  of  chromium. 
Mittler's  grim  (Ger.). 
Vert  panettier  (Fr.). 
Vert  de  Guimet  (Fr.). 
Vert  emeraude  (Fr.). 

Green  earth. 
Grim  erde  (Ger.). 
Terre  de  Verone  (Fr.). 
Terra  verde  (Ital.). 

{Chromium  sesquioxide. 
Opaque  oxide  of  chromium. 
Grimes  chromoxyd  (Ger.). 
Vert  de  chrome  (Fr.). 

Green  verditer. 

Green  bice. 

Mountain  green. 

Green  carbonate  of  copper. 

Berg  grim  (Ger.). 

Vert  de  Montagne  (Fr.). 

(Emerald  green .  D ££ K, &  f\ {}  N/ 

JCupric  aceto  arsenite. 
(Schweinfurts  grim  (Ger.). 
IVert  Paul  Verone  (Fr.). 

Cupric  arsenite. 
Swedish  green. 
Mittis  green. 
Scheele's  grim  (Ger.). 
Vert  de  Scheele  (Fr.). 

Basic  copper  acetate. 
Griinspan  (Ger.). 
Vert  de  gris  (Fr.). 
Vert  de  Montpelliers  (Fr.). 


The  Blue  Pigmenti 


Ultramarine  blue 


Chinese  blue 


New  blue. 
French  blue. 
Permanent  blue. 
Gmelin's  blue. 
Guimet's  blue. 
Lapis  lazuli  blau  (Ger.). 
Lasurestein  blau  (Ger.). 
Bleu  d'azur  (Fr.). 
Bleu  d'outremer  (Fr.). 

Soluble  blue. 


TABLE  OF  SYNONYMS 


187 


Prussian  blue 


Cobalt  blue 


Ceruleurn 


Chessylite 


Turner's  blue. 
Antwerp  blue. 
Berlin  blue. 
Prussiate  of  iron. 
Chinese  blue. 
Saxon  blue. 
Pariser  blau  (Ger.). 
Bleu  de  Berlin  (Fr.). 

fKobalt  blau  (Ger.). 
| Bleu  de  cobalt  (Fr.). 
[Bleu  de  Thenard  (Fr.). 

Coelin. 
Cerulian. 
Cerulean  blue. 
Coelin  blau  (Ger.). 
Blue  celeste  (Fr.). 

Blue  verditer. 

Bice. 

Mountain  blue. 

Azurite. 

Berg  blau  (Ger.). 

Cendres  bleus  (Fr.). 


Smalt 


Royal  blue. 

Dumont's  blue. 

Zaffre. 

Srnalte  (Ger.). 

Bleu  de  smalte  (Fr.). 


The  Brown  Pigments 


Raw  and  burnt  umber 


Raw  and  burnt  sienna 


English  umber. 
American  umber. 
Levant  umber. 
Turkish  umber. 
Cyprus  umber. 
Umbraun  (Ger.). 
Terre  d'ombre  (Fr.). 
Terra  ombra  (Ital.). 

Italian  sienna.      • 
American  sienna. 
Siena  erde  (Ger.). 
Terre  de  sienne  (Fr.). 
Terra  di  sienna  (Ital.). 


188  MODERN  PIGMENTS 


Vandyke  brown 


Cologne  earth. 
Cassel  earth. 
Collen  earth. 
Cassel  erde  (Ger.). 
Brun  de  Vandyke  (Fr.). 


The  Black  Pigments 

T  JRuss  (Ger.). 

Lamp  black |Noir  ^  fmnee  (Fr  }> 

Drop  black. 

Coach    black,  and    in    japan    or 

Ivory  black J     varnish  a  host  of  proprietary 

names . 

Elfenbein  schwartz  (Ger.). 
Noir  d'ivoire  (Fr.). 

Gas  black /Carbon  black;  in  oil  or  japan  and 

I    a  host  of  proprietary  names. 

[Blue  black. 

Vine  black. 
Charcoal  black {Frankfort  black. 

Frankfurter  schwartz  (Ger.). 
^Noir  de  vigne  (Fr.). 

Graphite- /Black  lead. 

(Plumbago. 


As  many  of  the  artist's  tube  colors  are  imported  from 
Germany  and  France,  such  as  De  La  Croix,  etc.,  it  was 
thought  best  to  give  the  names  of  most  pigments  in  the 
languages  of  those  countries  as  the  names  upon  the 
labels  are  in  those  languages. 


CHAPTER  XVIII 

VEHICLES  USED  IN  MIXING  PIGMENTS 
THE  FIXED  OILS 

PIGMENTS  require  various  thinning  liquids,  so  that  they 
can  be  applied  with  a  brush  to  the  surfaces  which  they 
are  to  cover  over.  These  liquids  must  possess  binding 
qualities  so  that  the  pigments  may  be  adhesively 
retained  upon  the  surfaces. 

Some  of  the  vehicles,  as  these  liquids  are  called,  possess 
within  themselves  the  requisite  binding  properties;  others 
do  not,  and  must  be  rendered  adhesive  by  the  addition  of 
other  substances  which,  when  mixed  intimately  with 
them,  make  them  artificially  adhesive  —  as  water,  for 
instance,  which  is  the  vehicle  used  for  distemper  painting. 

It  is  highly  proper  and  even  necessary  that  one  should 
know  something  of  what  is  required  from  the  various 
vehicles  used  in  painting,  and  why  one  is  used  for  certain 
purposes  in  preference  to  another. 

The  one  which  is  of  the  most  importance  in  connection 
with  outdoor  painting,  must  possess  some  well-defined 
qualifications,  as  otherwise  it  would  fail  to  do  what  is 
asked  of  it.  It  is  an  absolute  necessity  that  it  should 
contain  within  itself  perfect  adhesiveness,  which  will 
be  referred  to  as  binding  quality,  and  that  after  it 
dries  a  smooth,  waterproof  surface  may  be  obtained 
that  will  prevent  moisture  from  penetrating  into  the 

pigment  and  thus  affecting  the  surface  which  has  been 

189 


190  MODERN  PIGMENTS 

painted.  The  pigments  in  a  powdered  condition  are 
helpless  to  protect  themselves,  and  none  contain  adhesive- 
ness to  hold  to  the  side  of  a  building.  It  is  the  vehicle 
used  in  the  mixing  of  the  pigment  which  must  be  relied 
upon  to  do  the  binding. 

Pigments  indirectly  affect  the  durability  of  the  thin- 
ning liquids,  and  a  few  do  so  directly. 

For  outside  painting,  which  is  subject  to  all  the  inclem- 
encies of  the  weather,  —  heat,  moisture,  and  frost,  —  it  is 
obvious  that-  the  binding  vehicle  must  possess  water- 
proofing qualities  of  a  high  order.  It  must  harden  into 
a  solid  mass,  for  otherwise  the  paint  would  be  rubbed  off 
or  washed  away  by  rain. 

Nearly  all  oils  are  waterproof  and  will  shed  water; 
none  mix  readily  with  it;  but  only  a  few  have  the  prop- 
erty of  solidifying  into  a  hard,  waterproof  mass,  and  the 
oils  which  possess  this  power  are  called  fixed  oils. 

There  are  many  trees  and  plants  whose  seeds  give 
drying  or  fixed  oils,  such  as  the  walnuts,  hickories,  pecans, 
flax,  poppies,  and  others. 

Flax  and  poppy  are  the  only  plant  seeds  the  paint 
world  need  worry  about.  These  are  the  two  used  for  paint- 
ing, which  can  be  procured  at  a  reasonable  price  in  a 
commercial  way.  The  main  reason  for  this  is  that  oils 
can  be  expressed  from  them  much  more  cheaply  than 
from  any  other  known  plant  seeds.  Flaxseed  is  most 
abundantly  raised  as  a  field  crop,  and  its  cost  is  low 
compared  to  that  of  any  others,  not  excepting  poppy  seed. 
These  two  plants  possess  peculiarities  of  their  own  which 
make  them  more  desirable  than  any  other  for  the  making 
of  a  paint  oil. 

Besides  possessing  the  general  characteristics  which 
belong  in  common  to  all  fixed  oils,  each  of  these  (linseed 
and  poppy  seed)  has  its  own  which  make  them  differ 


VEHICLES  191 

from  each  other  and  from  every  other  of  the  fixed  oils  as 
well.  These  peculiarities  fit  each  one  of  these  oils  to  be 
better  adapted  to  a  certain  purpose  than  it  is  to  others, 
and  indicates  which  of  the  two  it  is  best  to  use  for  certain 
conditions.  While  poppy-seed  oil  is  superior  to  linseed 
oil  for  some  painting  (as  for  zinc  white  enameling),  it  is 
inferior  to  linseed  oil  (as  flaxseed  oil  is  universally  known 
in  English-speaking  countries).  This  and  the  other  very 
good  reason  that  linseed  oil  is  by  far  the  cheaper  of  the 
two,  are  the  main  causes  why  poppy-seed  oil  is  so  seldom 
used  in  general  painting.  There  can  be  no  question  as 
to  which  is  entitled  to  head  the  list  of  useful  vehicles. 

LINSEED  OIL 
Manufacture 

Linseed  oil  is  expressed  from  common  cultivated  flax- 
seed  (Linum  usitatissimum) .  This  is  grown  in  all  parts 
of  the  civilized  world.  It  grows  from  almost  the  sub- 
arctic regions  down  to  tropical  countries,  and  even  in 
these  in  elevated  regions. 

The  process  of  extracting  the  oil  from  the  seed  is  a 
very  simple  one,  and  once  every  little  town  or  hamlet 
had  its  crushing  mill  and  extracting  presses.  To-day  in 
this  business  as  well  as  in  that  of  every  other  commercial 
commodity,  the  manufacture  of  linseed  oil  is  in  the  hands 
of  large  concerns,  and  the  small  plants  have  gone  out  of 
the  business. 

The  flaxseed  is  ground  into  meal,  and  this  is  either  cold 
pressed  or  heated,  and  the  oil  pressed  out  of  it  by  powerful 
hydraulic  presses.  The  oil  flows  out,  and  the  solid  parts  of 
the  seed  remain  in  what  is  well  known  as  linseed-oil  cake. 

The  cold-pressed  oil  is  clearest,  palest,  and  best;  but  as 
by  that  process  it  cannot  be  made  to  yield  nearly  so  much 


192  MODERN  PIGMENTS 

oil  as  when  the  flaxseed  meal,  has  been  heated,  that  is 
very  seldom  practiced  now.  This  is  a  pity,  for  cold- 
pressed  linseed  oil  is  superior  for  painting  purposes,  and 
is  clearer,  more  fluid,  and  free  from  much  deleterious 
matter  which  is  extracted  by  the  hot  system. 

There  is  still  another  system  in  use  for  extracting  the 
oil  from  flaxseed,  and  a  still  greater  percentage  of  oil  is 
obtained  from  it  than  by  the  use  of  either  the  cold  or 
hot  system  of  pressing.  This  is  known  as  the  percolation 
process. 

After  the  grinding  of  the  flaxseed  into  meal,  this  is 
placed  into  a  percolating  tower  running  through  the 
several  stories  of  the  factory  building.  When  filled  with 
flaxseed  meal,  this  is  saturated  with  benzine  or  naphtha, 
and  more  of  that  subtle  fluid  is  poured  upon  the  meal  at 
the  top  of  the  tower.  This  is  continued  until  all  traces 
of  oil  have  been  dissolved  and  removed  from  the  meal. 
The  naphtha  charged  with  the  dissolved  linseed  oil  runs 
downward  to  the  bottom  of  the  tower  into  a  pipe,  which 
conducts  it  to  an  apparatus  where  it  is  heated.  The 
naphtha,  being  a  very  volatile  oil,  is  evaporated  at  a  com- 
paratively low  heat.  These  vapors  are  conducted  to 
condensers,  and  the  vapors  soon  condense  into  what  they 
were  originally  —  naphtha.  This  is  used  over  and  over 
again;  there  is  but  very  little  loss  of  it.  The  remaining 
oil  is  entirely  freed  from  the  naphtha  by  this  heating,  if  it 
is  properly  managed.  It  is  claimed  by  some  that  by 
this  system,  certain  substances  are  dissolved  which 
would  remain  undisturbed  by  pressure,  and  that  the  loss 
injures  the  durability  of  the  linseed  oil  for  outdoor  work. 
This  claim,  however,  may  not  be  well  founded,  and  may 
be  due  to  prejudice  or  the  self-interest  of  concerns  that 
press  oil.  Some  again  claim  that  it  is  better.  However, 
so  many  from  all  parts  of  the  country  claim  differently, 


VEHICLES  193 

that  one  should  be  slow  in  making  the  change  from  one 
to  the  other.  Experiment  with  them  side  by  side  under 
varied  conditions.  This  system  has  some  good  points  in 
it.  Naphtha  does  not  dissolve  moisture,  and  linseed  oil 
thus  made  is  as  nearly  free  from  it  as  it  is  possible 
for  it  to  be,  and  this  cannot  be  said  of  the  heat- 
expressed  oils.  The  real  difference  between  the  pressed 
oil  obtained  by  heat  and  the  percolated  oil,  cannot 
be  so  great  as  to  deter  any  one  from  using  either,  but 
the  chances  are  that  the  old-fashioned  cold-pressed  oil  is 
the  best. 

Linseed  oil  made  by  whatever  system,  may  vary  a 
good  deal  in  its  quality  from  other  causes  than  those 
pertaining  to  the  system  of  extraction.  It  varies  greatly 
accordingly  as  it  is  made  from  good  or  from  bad  flax- 
seed.  That  made  from  East  Indies,  imported  flaxseed 
(better  known  as  Calcutta  seed,  from  the  city  from  which 
it  comes)  is  usually  better  than  that  obtained  from  Ameri- 
can seed.  Its  product,  sold  as  Calcutta-seed  oil,  is  usually 
freer  from  moisture  than  that  which  is  made  from  flax- 
seed  of  American  or  Russian  origin.  Varnish  men  who 
ought  to  be  good  judges  of  quality  in  linseed  oil,  prefer 
it  to  all  others,  in  the  preparation  of  varnishes,  as  they 
must  have  a  dry  oil,  containing  but  little  moisture. 
American  flaxseed,  when  properly  harvested,  is  as  good 
as  any  in  the  world  —  but  there  is  the  trouble,  it  is  not 
harvested  properly.  In  America,  flaxseed  is  harvested  by 
machinery,  the  same  as  wheat.  Owing  to  the  ease  with 
which  it  shells  out  when  the  sickle  strikes  the  plant,  the 
cutting  cannot  be  delayed  until  the  seed  is  ripe,  as  it 
would  all  shell  out  and  fall  to  the  ground;  so  the  crop  is 
cut  down  before  it  is  ripe,  just  as  the  seed  begins  to  change 
from  the  dough  state  and  begins  to  harden.  In  that 
ccndition,  it  is  saved  without  shelling  —  but  it  is  far  from 


194  MODERN  PIGMENTS 

being  fully  ripe.  In  the  East  Indies,  where  labor  is  very 
cheap,  it  is  pulled  by  hand,  when  the  proper  times  comes, 
and  thus  they  are  able  to  secure  it  in  the  very  best  con- 
dition. This  is  impossible  in  America,  hence  American 
seed  does  not  equal  it. 

So  with  poor  seed  to  start  with,  and  a  larger  quantity 
of  oil  expressed  out  of  it  than  in  the  good  old  days  of 
cold  presses,  there  can  be  no  wonder  at  the  complaints 
that  linseed  oil  does  not  wear  as  well  to-day  as  it  did  in 
old  times. 

For  good  work,  it  would  pay  to  use  cold-pressed  oil, 
even  at  an  expense  of  several  cents  more  per  gallon.  It 
would  pay  architects  to  specify  it  in  their  contracts,  and 
property  owners  should  be  willing  to  foot  the  slight 
increase  it  would  make  in  their  painting  bill,  if  they 
could  only  be  made  sure  that  they  were  getting  it  after 
specifying  it  and  paying  for  it.  But  quien  sdbe? 

Linseed  oil,  after  it  has  been  pressed,  should  be  tanked 
for  three  or  four  months  to  allow  it  to  deposit  some  of 
the  foreign  matter  pressed  out  of  the  seed  with  the  oil, 
and  with  which  it  is  more  or  less  charged.  This  will 
settle  to  the  bottom  of  the  tanks,  and  is  called  linseed-oil 
foots.  It  will  do  so  naturally,  if  only  time  enough  be  given 
—  but  it  is  not  allowed. 

Manufacturers  being  human  (in  some  ways)  do  not  take 
kindly  to  the  idea  of  having  vast  sums  of  money  tied  up 
for  several  months  in  a  tank.  They  want  to  turn  that 
money  over  and  over  before  the  oil  would  be  fit  to  sell  in 
the  natural  way  it  has  of  doing  this  work,  so  they  arti- 
ficially hasten  this  precipitation. 

There  are  two  ways  of  doing  this;  one  is  known  as  the 
alkaline  process.  As  this  is  the  poorer  of  the  two,  no 
time  will  be  wasted  upon  it.  The  other  is  by  trituration 
with  sulphuric  acid. 


VEHICLES  195 

Sulphuric  acid  does  not  affect  linseed  oil  injuriously,  and 
it  acts  only  upon  the  impurities  which  precipitate  rapidly. 
The  oil  is  then  well  washed  with  water  by  trituration 
until  it  is  free  from  traces  of  acid,  and  is  then  considered 
fit  for  use.  Varnish  manufacturers  who  are  most  careful 
in  the  purchase  of  linseed  oil  usually  still  further  refine  the 
oil  by  repeated  agitation  of  it  with  sulphuric  acid;  and  the 
grinders  of  fine  pigments  requiring  refined  oil,  use  it  also 
for  the  same  purpose.  With  both  of  these  sets  of  men, 
clearness  and  limpidity  are  of  the  first  importance;  but 
painters  of  the  old  school  who  can  remember  the  time 
when  they  went  to  the  town  mill  and  bought  cold-pressed 
oil  settled  in  the  old-fashioned  way,  and  used  it  to  mix 
their  pigments  with,  claim  that  three  coats  of  such  oil 
and  white  lead  would  wear  for  years  before  it  would  com- 
mence to  chalk.  Now  a  like  number  of  coats  prepared  in 
the  old  way,  but  with  oil  such  as  it  now  is,  will  appear  as 
so  much  whitewash  in  the  same  number  of  years.  It 
will  require  something  else  besides  plausible  talk  to  make 
them  believe  that  the  oil  they  buy  to-day  is  half  as  good 
as  the  old-fashioned,  cold-pressed,  naturally  settled  oil 
made  from  pulled  flax  which  it  was  possible  for  them  to 
buy  some  seventy  years  ago. 

Chemistry  of  Linseed  Oil 

Linseed  oil  is  a  complex  product,  and  its  drying  or 
solidifying  is  due  to  its  becoming  oxidized.  Condit  says: 
"To  understand  the  action  that  occurs  when  oil  dries, 
we  must  know  the  composition  of  it.  Linseed  oil  is 
composed  of  linolein,  palmittin,  and  olein.  To  non- 
chemists,  these  words  are  mere  names;  but  let  us  designate 
linolein  by  A,  palmittin  by  B,  and  olein  by  C;  now  A  the 
first  is  composed  of  linoleic  acid  and  glycerine  ether, 
B  of  palmitic  acid  and  glycerine  ether,  and  C  of  oleic  acid 


196  MODERN  PIGMENTS 

and  glycerine  ether.  Glycerine  ether  is  the  base  to 
which  the  other  constituents  are  attached.  Looking  upon 
glycerine  as  D,  we  may  represent  the  other  constituents 
as  allotted  in  this  manner: 

A  — 

B 


=D 


Chemically  considered,  these  salts  (A,  B,  and  C)  are  sus- 
ceptible of  parting  with  their  base  glycerine  (D)  in  favor 
of  some  base  possessing  a  stronger  affinity  for  oily  acids." 

The  Drying  of  Linseed  Oil 

"This  kind  of  decomposition  in  point  of  fact  really 
takes  place  under  proper  conditions,  and  the  resulting 
soap  varies  in  its  nature  according  to  the  base  employed. 
Take  an  instance:  Suppose  you  have  rubbed  some  linseed 
oil  on  a  sheet  of  glass  or  china  (I  mention  these  substances 
to  preclude  the  idea  of  the  absorbance  of  any  part  of  the 
oil  which  would  take  place  if  wood,  etc.,  were  used)  and 
it  has  sufficiently  dried  not  to  become  sticky,  and  that 
when  in  that  condition  you  wash  it  with  a  solution  of  soda 
in  water,  the  soda  dissolves  the  glycerine  to  unite  with 
the  oily  acids  (linoleic,  palmitic,  and  oleic)  and  forms  a 
soap,  leaving  the  glycerine  free.  In  other  words,  using 
the  above  formula:  A,  B,  and  C  unite  with  the  soda  (or 
other  alkali)  and  leave  D  a  free  agent.  Now  this  D  is 
soluble  in  water,  consequently  the  soap  which  is  formed 
(by  the  union  of  A,  B,  and  C  with  the  alkali)  is  also  dis- 
solved. This  soap,  by  the  way,  is  not  like  the  ordinary 
hand  soap,  but  is  a  frothy  matter  that  gathers  on  the 
glass.  Hence,  by  washing  the  oil  with  sufficient  soda  and 
water,  every  trace  of  oil  is  carried  away  from  the  glass." 

The  above  explains  what  would  take  place  if  the  oil 
were  left  in  an  undried  state,  and  to  some  extent  what  does 


VEHICLES  197 

take  place  when  linseed  oil  is  washed  over  with  alkalies 
even  when  dry.  It  is  the  same  action  which  takes  place 
when  the  alkaline  removers  take  off  paint;  but  to  return 
and  find  out  how  oil  dries,  Condit  further  says: 

"  In  speaking  of  the  drying  of  linseed  oil  merely  a 
change  from  the  liquid  to  the  solid  state  is  meant.  Now 
the  constituents  of  the  four  components  of  linseed  oil 
consist  of  oxygen,  hydrogen,  and  carbon  in  varying  pro- 
portions; that  is,  linoleiu  A,  palmittin  B,  and  olein  C  are  all 
made  up  of  the  above  elements,  differing  in  proportion 
just  as  the  letters  A,  B,  and  C  are  made  up  of  straight  lines 
and  curves,  differing,  however,  from  each  other  in  the 
totality. 

"Now  in  the  change  from  the  fluid  to  the  solid  con- 
dition, i.e.,  the  drying  process,  oils  suffer  a  slight  loss  of 
carbon  and  oxygen,  but  they  gain  about  one  tenth  of 
their  own  weight  in  oxygen.  It  is  by  this  union  of  oxygen 
with  the  component  of  linseed  oil  that  they  dry  or  harden. 
Put  them  out  of  the  influence  of  this  element  and  they 
remain  fluid.  Slow-drying  oils  lose  least  in  weight;  they 
contain  more  of  the  non-drying  fats,  and  for  that  reason 
seem  to  gain  more  in  weight  (in  time)." 

The  process  of  drying,  while  it  is  very  simple,  in  theory 
at  least,  is  most  intricate,  and  would  require  too  many 
explanations  to  follow  it  up  in  all  its  details,  so  it 
cannot  be  given  here  as  fully  as  some  might  wish.  To 
properly  handle  the  subject  would  require  a  large 
volume,  therefore  a  resume  is  given  below  in  short 
paragraphs,  which  contains  the  gist  of  the  process;  it,  too, 
is  from  Condit : 

"  1.  Linseed  oil  is  composed  of  linolein  drying  oil,  80 
parts;  palmittin  and  olein  non-drying  oils,  20  parts,  of 
which  8  parts  are  glycerine  ether  which  flies  away  in  the 
process  of  drying. 


198  MODERN  PIGMENTS 

"2.  Pure  oil  will  not  dry  in  darkness;  and  the  greater 
the  light,  the  more  vigorous  the  drying. 

"3.  Heat  is  also  a  powerful  drier  of  oil;  oils  heated 
for  a  short  time  continue  to  dry  more  rapidly  for  a  long 
time  after  the  heating. 

"4.  Drying  appears  to  be  the  loss  of  glycerine  ether 
and  the  gain  of  oxygen  from  the  air,  the  glycerine  appear- 
ing to  be  loosened  from  the  oil  acid  as  the  oxygen  unites 
with  the  oil,  the  result  of  the  drying  being  a  light  varnish. 

"5.  Some  of  the  non-drying  oil  acid  also  flies  away  in 
the  drying,  especially  under  the  influence  of  direct  sun- 
light or  when  the  oil  is  heated;  100  parts  of  oil  become 
111  parts  (more  or  less)  heated;  it  loses  3  parts  (more 
or  less);  net  gain  8  parts. 

"6.  Most  of  the  glycerine  ether  which  is  linked  with 
the  oil  flies  away  in  the  drying. 

"7.  When  oxygen  combines  with  a  drying  oil  —  that 
is,  a  fixed  oil  —  caoutchou  or  gluten  is  produced,  which 
in  reality  is  the  hard,  horny,  elastic  body  that  renders  it 
'dry.'  It  is  the  '  skin'  that  forms  on  top  of  a  pot  of  paint 
when  it  has  been  left  undisturbed  for  some  time. 

"8.  The  drying  of  oils  appears  to  depend  upon  the 
presence  of  oxygen,  which,  by  an  incipient  combustion 
of  hydrogenous  oils,  fixes  them.  Whatever  contributes 
oxygen  is  a  drier,  as  is  the  case  with  pure  air,  sunshine, 
etc.  So  also  the  perfect  oxides  of  metals,  including  even 
pure  earths  and  alkalies  in  due  proportion,  dry  oils;  the 
best  are  those  which  contain  oxygen  in  excess,  such  as 
litharge,  sugar  of  lead,  minium  or  red  lead,  the  oxides  of 
manganese,  sulphate  of  zinc,  white  copperas  and  verdigris." 

Properties  and  Uses 

Raw  linseed  oil  is  penetrating  and  elastic,  and  after  its 
oxidation  or  drying  it  remains  as  a  waterproof  rubber- 


VEHICLES  199 

like  substance,  holding  firmly  whatever  pigment  it  has 
been  mixed  with.  Some  pigments  act  chemically  upon 
it,  as,  for  instance,  the  lead  salts,  which  have  the  property 
of  turning  it  into  a  soap,  which,  however,  is  not  a  readily 
soluble  one  (after  drying  at  least);  the  lead  oxides  are 
noted  for  this  property,  as  red  lead  and  litharge.  Not- 
withstanding that  a  great  deal  has  been  said  as  to  the 
beneficial  influence  exerted  by  the  totally  inert  pigments 
—  which  in  a  measure  is  true  —  it  is  equally  true  that 
some  very  active  ones,  combining  chemically  with  lin- 
seed oil,  exert  a  very  good  influence  over  it,  as  occurs  when 
red  lead  and  linseed  oil  are  combined,  the  resulting 
linoleate  soap  being,  when  dry,  insoluble  in  water.  It 
is  not  acted  upon  injuriously  by  that  element,  which  is 
most  destructive  to  linseed  oil  ordinarily.  This,  how- 
ever, is  not  true  of  all  active  pigments,  some  of  them 
exerting  baneful  influences  upon  linseed  oil  as  they  com- 
bine with  it  to  form  soluble  soaps.  Pigments  containing 
lime  in  a  caustic  form  are  of  that  character. 

The  inert  pigments  naturally  do  not  exert  any  influ- 
ence upon  it  one  way  or  another,  and  when  linseed  oil 
has  been  mixed  with  them  no  chemical  action  takes 
place;  the  drying  and  longevity  of  the  oil  remain  the 
same,  generally  speaking,  as  if  the  pigments  had  not 
been  added. 

The  above  statement  was  purposely  qualified  by  saying 
generally  speaking,  because  in  one  way  they  do  exert  an 
influence  which,  while  it  is  not  chemical,  is  a  mechanical 
one,  in  this  way:  Some  pigments  are  very  heavy  and  have 
no  affinity  for  oil,  and  naturally  take  up  but  little  when 
mixing  them  into  a  paint;  others  again  are  very  light 
and  take  up  large  quantities.  It  is  reasonable  to  suppose 
then  that  the  pigment  which  has  not  taken  up  much  oil 
will  be  a  drag  upon  the  oil,  as  a  little  of  it  is  scattered  over 


200  MODERN  PIGMENTS 

a  great  quantity  of  pigment  atoms,  so  that  but  an  infin- 
itesimal portion  has  to  perform  a  duty  that  is  above 
its  strength,  and  so  it  is.  Such  pigments  cannot  be 
depended  upon  for  outdoor  work. 

On  the  other  hand,  the  pigment  which  holds  up  large 
quantities  of  oil  mechanically  prolongs  its  life. 

Again,  there  is  a  class  of  pigments  containing  non- 
drying  elements  in  their  composition,  which  prevent  the 
oil  from  drying,  such,  for  instance,  as  uncalcined  lamp 
black,  vandyke  brown,  etc.  These  cannot  be  safely  used 
without  first  preparing  the  oil,  so -that  it  shall  contain 
sufficient  drying  energy  to  overcome  their  deficiencies. 
Artificial  driers  must  be  added  to  the  oil  to  hasten  its 
drying.  Otherwise,  these  pigments  exert  a  good  influ- 
ence upon  the  longevity  of  the  oil,  as  they  take  up  so 
much  of  it. 

Linseed  oil  continues  to  absorb  oxygen  after,  seem- 
ingly, it  is  as  dry  as  it  is  possible  for  it  to  be,  or  long  after 
it  has  ceased  to  feel  tacky  to  the  touch.  The  fact  is  that 
when  it  has  reached  that  stage  where  no  further  oxida- 
tion takes  place  then  its  downward  grade  of  decay  may 
be  said  to  have  commenced. 

Linseed  oil,  while  it  may  not  be  as  good  as  it  was  fifty 
years  ago,  when  it  was  all  cold  pressed,  is  usually  found 
pure,  such  as  it  is.  It  is,  of  course,  possible  for  some  of 
the  dealers  to  practice  the  adulteration  of  it,  but  it  is 
seldom  that  that  occurs.  Jobbers,  in  the  past  (a  few  of 
them),  who  did  not  care  for  reputation,  did  mix  oils,  but 
now  such  a  thing  is  next  to  impossible.  What  with 
nearly  every  state  having  special  laws,  which  no  one 
would  take  any  risk  of  infringing,  and  behind  these  Uncle 
Sam  with  his  own  strict  laws  to  prevent  fraud  —  the 
practice  of  adulterating  linseed  oil  has  about  become 
obsolete. 


VEHICLES  201 

Linseed  oils  are,  however,  imitated;  but  the  imitations 
are  sold  as  such.  There  can  be  no  harm  come  of  it,  for 
no  one  is  cheated.  If  a  painter  is  foolish  enough  to 
believe  all  the  stuff  that  smooth-tongued  strangers  tell 
him  regarding  the  merits  of  nonpareil,  indestructible 
enamelling  liquid,  in  the  way  of  throwing  linseed  oil  in 
the  shade,  and  supplanting  it  everywhere,  he  has  a  perfect 
right  to  believe  and  to  give  his  money  away  for  it.  The 
law  recognizes  him  as  a  free  agent  and  will  not  forcibly 
keep  him  from  flinging  cash  in  the  river,  if  he  so  wills. 
It  takes  money  to  buy  experience,  and  with  some  men 
it  only  seems  to  last  until  the  next  deceiver  comes  around 
with  another  bait  —  10  cents  a  gallon  below  the  market 
on  linseed  oil! 

Barnum  said:  "For  every  fool  that  dies,  two  are  born." 
It  must  be  true,  or  the  concerns  manufacturing  dope  oil 
could  not  flourish  as  they  do. 

Impurities,  and  Tests  for  Them 

It  is  a  very  hard  matter  to  determine  impurities  in 
linseed  oil,  and  nothing  short  of  an  analysis  made  by  an 
expert  chemist  used  to  that  sort  of  work  will  be  of  any 
value.  This  work  is  intricate  and  expensive.  But 
anyone  can  readily  determine  to  his  own  satisfaction 
whether  linseed  oil  is  adulterated  or  not.  At  least, 
raw  linseed  oil  can  be  so  tested,  but  not  the  boiled. 
There  is  no  test  that  one  can  make  for  himself  that  will 
do  .for  that. 

There  are  several  tests.  One,  the  most  usual,  is  the 
nitric  acid  test.  Although  it  is  a  simple  one  to  make,  it 
is  apt  to  lead  many  into  error,  if  they  are  unused  to 
testing  oils.  To  make  the  test:  Take  a  bottle,  or  any 
other  glass  vessel,  pour  into  it  about  equal  parts  of  raw 
oil  and  nitric  acid  —  one  ounce  of  each  is  enough  for  the 


202  MODERN  PIGMENTS 

purpose.  Shake  the  bottle,  so  as  to  mix  the  oil  and  acid 
well  together,  and  put  it  away  to  rest  for  a  quarter  of  an 
hour.  If  the  oil  is  pure,  the  nitric  acid  will  settle  at  the 
bottom  of  the  bottle,  where  it  forms  a  distinct  layer 
below  the  oil  which  floats  on  top.  The  nitric  acid  in  a 
well-made  oil  will  be  found  clear,  but  tinged  to  a  light 
straw,  from  coloring  matter  extracted  from  the  oil  during 
the  shaking;  the  oil  itself  in  the  upper  layer  will  be- found 
to  have  turned  to  a  brownish  color,  but  of  a  clear  tone. 
If  adulterated,  the  oil  will  be  from  dark  brown  to  black 
and  muddy,  lumpy  or  "livered,"  according  to  the  nature 
of  the  adulterant.  The  acid  will  be  brownish,  and  often 
its  limpidity  even  will  be  impaired;  but  not  always  so, 
this  depending  also  upon  the  nature  of  the  adulterating 
oils.  It  is  impossible  thus  to  determine  the  adulterant 
that  requires  a  chemical  analysis. 

Then  there  is  the  specific  gravity  test,  which  is  always 
satisfactory,  as  it  is  a  very  hard  matter  to  adulterate  oils 
so  that  this  will  not  be  greatly  changed.  It  requires 
apparatus  to  make  this  test,  but  that  is  not  very  expen- 
sive: a  suitable  hydrometer,  one  that  is  adapted  to  oils 
or  fats,  with  a  thermometer,  are  all  that  will  be  needed. 
The  oil  should  be  poured  into  a  vessel,  which  must  be 
considerably  deeper  and  wider  than  the  hydrometer, 
which  is  dropped  into  it,  and  which  must  float  clear  of 
the  sides  and  the  bottom  of  the  oil  receptacle.  The 
specific  gravity  of  linseed  oil  is,  say,  0.932  at  60°  F.  Now 
if  the  hydrometer  is  placed  in  the  oil  and  the  top  of  the 
bulb  indicates  .928  or  .934,  if  the  temperature  of  the  oil  is 
either  above  or  below  60°  F.,  a  correction  must  be  made 
for  that,  as  the  oil  will  show  a  lighter  gravity  if  below  the 
standard  temperature  and  heavier  if  above.  Deduct  or 
add  .00035  for  each  degree  of  variation  in  temperature 
either  above  or  below  the  standard,  and,  if  the  oil  is  pure, 


VEHICLES  203 

the  total  ought  to  be  0.932.     If  it  varies  very  much,  the 
oil  is  adulterated. 

Then  there  is  the  flash  test,  but  this  is  rather  com- 
plicated and  requires  more  apparatus  to  determine  cor- 
rectly. The  two  above-mentioned  tests  will  be  sufficient. 
Besides,  the  nose  and  the  eye  can  be  made  nearly  as 
efficient  as  any,  at  least  for  certain  kinds  of  adulterants. 
Linseed  oil  has  a  smell  all  its  own,  and  neutral  oils  can  be 
readily  detected  by  their  odor  with  the  nose,  they  have 
also  a  bluish  fluorescent  tone  that  the  eye  can  readily 
note,  so  that,  with  the  help  of  these  organs,  a  double  test 
can  be  made,  and  one  or  the  other  will  be  apt  to  uncover 
the  adulteration.  The  nose  will  also  detect  animal  or 
fish  oils,  which  may  be  used  in  adulterating;  however,  the 
chances  are  that  it  will  be  hard  to  find  any  as  long  as  they 
stay  above  the  cost  of  linseed  oil. 

BOILED  OIL 

As  it  has  already  been  stated  the  heating  of  linseed 
oil  renders  it  more  drying.  When  it  is  boiled  at  a  great 
heat  along  with  some  of  the  oxides  of  lead  or  manganese 
it  is  rendered  thereby  still  more  drying. 

For  mixing  with  some  of  the  non-drying  pigments, 
its  use  is  imperatively  demanded,  at  least  for  the 
grinding  of  them  into  pastes.  Boiled  oil  is  less 
elastic  than  raw  oil,  and,  being  darker,  it  tinges 
the  white  pigments  and  some  of  the  light  tints  to 
an  undesirable  degree.  It  is  also  much  less  elastic 
than  raw  oil  and  less  penetrating,  therefore  it  should 
never  be  used  for  priming  purposes.  It  partakes  of  the 
nature  of  a  varnish,  and  dries  upon  the  surface  with  but 
little  penetration. 

It  is  therefore  better  adapted  for  interior  painting  than 
it  is  for  that  of  outside  work.  Its  use  is  indicated,  how- 


204  MODERN  PIGMENTS 

ever,  for  many  purposes  where  penetration  and  elasticity 
are  not  of  prime  importance. 

Adulteration 

Under  the  heading  of  raw  oil,  it  was  said  that  all  tests 
which  were  indicated  for  that  were  useless  when  applied 
to  boiled  oil,  and  so  they  are.  It  requires  an  expensive 
chemical  analysis.  Unless,  of  course,  that  the  adulterat- 
ing has  been  so  carelessly  done  that  the  nose  and  eye  can 
be  utilized  to  ferret  it  out,  as  is  the  case  when  neutral 
oils  have  been  added. 

The  most  frequent  adulteration,  if  adulteration  it  be, 
is  in  many  dealers  taking,  say,  one  barrel  of  raw  linseed 
oil  pouring  the  contents  of  it  into  the  boiled  oil  tank  and 
adding  from  five  to  ten  gallons  of  some  cheap  benzine 
manganese  dryer.  Boiled  oil  thus  prepared  is  called 
bung  hole  boiled  oil.  It  is  simply  raw  oil  with  probably 
a  bigger  dose  of  liquid  drier  than  would  have  been  the 
case  if  the  painter  had  added  it  himself. 

POPPY  SEED  OIL 

Properties  and  Uses 

As  the  name  implies,  this  excellent  paint  oil  is  produced 
from  the  seed  of  the  poppy  plant  —  opium  poppy,  or 
papaver  somniferum.  It  is  nearly  colorless  and  very 
clear,  so  these  qualities  render  it  of  great  value  for  the 
mixing  of  white  pigments  or  for  that  of  tender 
light  tints.  For  China  finish  or  interior  enameling, 
for  instance,  it  is  invaluable.  In  this  connection 
it  should  be  used  with  zinc  white  in  preference  to 
linseed  oil,  which  has  the  property  of  darkening  the 
more  quickly  that  it  is  shut  away  from  the  sun's 
rays.  This  defect  does  not  belong  to  poppy  seed  oil. 


VEHICLES  205 

Zinc   white  of  good   quality  is  ground  in  it  to  a  paste 
form,  and  so  labeled  when  offered  for  sale. 

Poppy  seed  oil  is  a  slow  drier,  so  it  requires  a  longer 
time  for  paint  mixed  with  it  to  become  dry.  Its  binding 
properties  are  no  better  than  are  those  of  linseed  oil  — 
if  as  good.  Its  high  cost  compared  to  that  of  linseed  oil 
will  always  prevent  its  use.  It  is,  therefore,  but  for 
expensive  enameling  that  its  use  is  ever  resorted  to  by 
the  general  painter  and  decorator.  Artists,  of  course,  can 
afford  to  use  it,  ad  libitum,  in  the  very  small  quantities 
they  require. 


CHAPTER  XIX 

VEHICLES     (Continued) 

THE  VOLATILE  OILS 

Spirits  of  Turpentine 

IN  defining  the  word  vehicle,  it  was  stated  that  it  was 
a  liquid  medium  with  which  pigments  were  mixed  and 
properly  thinned,  so  that  they  could  be  spread,  by  paint- 
ing with  a  brush,  over  the  surfaces  to  which  the  painter 
wished  to  apply  them;  that,  through  their  agency,  the 
pigments  were  made  steadfast  to  these  surfaces  by  those 
adhering  or  binding  qualities  of  the  vehicles,  either  pos- 
sessed inherently  within  themselves,  or  added  to  them  by 
the  introduction  and  admixture  of  binding  agents,  as 
glue  or  gum  arabic,  etc.,  for  water;  the  volatile  oils 
serve  another  purpose  in  painting. 

Their  binding  qualities  are  little  better  than  water. 
This  can  readily  be  inferred  from  the  fact  that  they 
evaporate  entirely  away,  so  that  pigments  mixed  with 
them  alone  would  have  about  the  same  chance  of  remain- 
ing upon  outside  surfaces  as  they  would  have  if  they  were 
mixed  with  water  instead  —  till  the  next  hard  rain  came, 
which  would  wash  them  away;  or  some  boy,  even,  without 
the  rains,  could  rub  the  painting  off  with  his  bare  hand. 

The  chief  use  of  volatile  oils  in  painting  is  for  the  pur- 
pose of  rectifying  some  defects  in  the  fixed  oils  that  are 
used  as  binding  vehicles  in  exterior  painting,  and  for 
what  is  called  flatting  in  interior  work. 

206 


VEHICLES  207 

As  adjuncts  to  linseed  or  poppy  seed  oils,  they  possess 
the  property  of  intimately  mixing  with  them,  and  of  ren- 
dering them  more  fluid  (they  lessen  their  viscosity)  and 
also  make  the  fixed  oil  set  quicker.  This  enables  the 
painter  to  put  on  a  heavier  coat  of  pigment  with  less 
linseed  oil  than  would  be  possible  without  the  use  of  the 
volatile  oils. 

For  flatting  purposes  they  are  used  as  the  main  vehicle, 
A  sufficient  quantity  of  linseed  oil  must  be  used  to  bind 
the  pigment.  It  requires  little  to  accomplish  that  purpose, 
so  that  finishing  coats  of  flatting  are  nearly  entirely  of 
volatile  oil.  As  flatting  is  usually  done  over  a  gloss 
coat  —  one  containing  considerable  linseed  oil  —  unless 
the  flatting  is  delayed  until  the  gloss  coat  has  dried  hard, 
there  will  be  enough  tack  in  that  to  hold  the  flatting 
thinned  almost  entirely  with  volatile  oil.  If,  however, 
one  waits  till  it  has  thoroughly  hardened,  a  small  quantity 
of  linseed  oil  must  be  added  to  the  flatting  coat. 

Spirits  of  Turpentine 

Spirits  of  turpentine  is  the  commercial  term  used  in 
the  United  States  to  designate  what  the  painter  calls 
turps  at  the  shop.  In  England,  it  is  best  known  as  oil 
of  turpentine,  which  it  really  is.  Both  names  refer  to  the 
same  liquid. 

It  is  obtained  from  several  species  of  pines.  That 
which  has  been  so  abundantly  produced  in  America  is 
derived  entirely  from  the  longleaf  yellow  pine  of  the  tide- 
water section  of  the  Southern  States  adjoining  the 
Atlantic  and  the  Gulf  of  Mexico.  It  is  produced  on  a 
large  scale  by  scarifying  the  trees  and  collecting  the 
exuding  gum  which  gathers  at  the  wounds.  This  gum  is 
a  highly  odoriferous  semi-solid  resin.  This  is  gathered 
and  hauled  away  to  refining  works,  where  it  is  distilled. 


208  MODERN  PIGMENTS 

The  volatile  vapors  are  cooled  and  condensed  into  the 
spirits  of  turpentine,  while  the  solid  parts  remain  as 
rosin  of  many  grades  of  goodness,  according  as  it  is 
very  light  or  dark  colored  —  the  whitest  being  the  most 
valuable. 

Spirits  of  turpentine  is  the  most  valuable  of  the  volatile 
oils  used  by  the  painter.  Its  odor,  while  it  is  strong  and 
penetrating,  is  far  from  being  disagreeable,  and  unless  it 
is  used  during  hot  weather  in  a  close  room  it  is  not 
unhealthy  as  are  those  oils  derived  from  petroleum 
distillation. 

Spirits  of  turpentine  acts  promptly  upon  the  urinary 
organs,  and  it  is  strongly  diuretic  in  action.  Some  men 
seem  to  be  much  more  readily  affected  by  it  than  others 
—  some  are  so  to  the  extent  that  they  cannot  endure  to 
work  with  it  long  at  a  time;  others  again  have  worked 
with  it  daily  for  years  without  being  detrimentally 
affected  by  it.  Persons  who  are  troubled  with  kidney 
diseases  should  be  careful  in  its  continued  use.  It  is 
not  only  absorbed  by  direct  contact  through  the  pores 
of  the  skin,  but  also  by  the  inhaling  of  its  vapors,  which 
soon  permeate  the  atmosphere  of  a  room  where  it  is  used, 
and  where,  as  in  flatting,  little  outside  air  is  allowed  to 
enter,  and  then  it  is  inhaled  at  every  breath  in  large 
quantities. 

NAPHTHA  AND  BENZINE 

Properties  and  Uses 

For  the  purposes  of  painting,  these  two  volatile  oils 
may  be  treated  together.  Both  are  so  nearly  the  same 
in  composition,  working  qualities  and  odor,  that  they 
may  be  regarded  as  the  one  thinning  vehicle  in  paint 
mixing.  They  are  both  derived  from  the  distillation  of 
petroleum,  and  in  early  days  were  in  very  bad  repute. 


VEHICLES  209 

They  possess  the  properties  ascribed  to  the  volatile 
oils  useful  in  paint  mixing,  and  described  under  the 
heading  of  Spirits  of  Turpentine.  They  do  not,  any  more 
than  turpentine,  possess  any  binding  properties.  As 
diluents  of  linseed  oil,  they  are  as  good  as  and  in  some  re- 
spects better  than,  spirits  of  turpentine,  and  in  one  instance 
they  are  not  so  good. 

They  are  better,  in  that  it  takes  less  to  accomplish  the 
purpose  for  which  they  are  used  (the  only  legitimate  use 
that  can  be  made  of  volatile  oils  in  paint),  that  of  making 
a  paint  more  liquid  —  spreading  better. 

But,  phew!  The  smell!  That  is  where  the  inferiority 
comes  in.  Their  odor  is  repugnant  to  many  persons,  and 
to  a  few  it  is  equal  to  a  dose  of  lobelia  or  tartar  emetic. 
They,  too,  act  upon  the  kidneys  and  urinary  organs,  but 
not  in  such  a  marked  manner  as  spirits  of  turpentine, 
and  in  addition  they  more  than  tax  the  stomach.  For 
outside  painting,  they  are  better  than  turpentine,  for  the 
reason,  already  given,  that  it  takes  less  to  dilute  the  paint, 
so  that  more  oil  can  be  used  and  applied,  and  consequently 
the  paint  will  not  flat  out  so  quick.  It  evaporates  some- 
what more  quickly  and  sets  the  paint  in  a  shorter  time  — 
another  advantage. 

The  better  grades  of  these  oils  are  treated  with  a  view 
to  removing  the  disagreeable  smell  inherent  in  them,  and 
while  thus  treated  they  do  not  smell  nearly  as  bad  as 
those  which  have  not  been  deodorized;  there  is  room  for 
vast  improvement  in  this  respect.  There  is  hope  enter- 
tained of  this.  Spirits  of  turpentine  is  becoming  scarcer 
and  higher  every  day,  and,  at  the  rate  that  the  Southern 
forests  are  disappearing  under  the  ax  of  the  lumberman, 
it  is  only  a  question  of  a  few  years  when  the  quantity  of 
it  obtainable  will  be  so  small  and  its  price  will  have  soared 
so  high  that  it  cannot  possibly  be  employed,  as  it  was  by 


210  MODERN  PIGMENTS 

the  general  painter.  In  quantity  it  will  have  dwindled 
down  to  where  there  will  scarcely  be  enough  of  it  left  to 
supply  the  demand  of  the  pharmacists  of  the  world,  who 
all  look  to  the  United  States  for  their  main  supply. 

When  that  time  arrives, —  and  it  is  plainly  in  sight  now, 
willy-nilly,  —  naphtha  and  benzine  must  ta"ke  its  place. 
If  completely  deodorized,  there  will  be  no  loss  —  at  best, 
one  might  as  well  become  accustomed  to  their  use  now; 
and  artists,  decorators,  and  others  might  as  well  quit 
shedding  tears  and  accept  the  inevitable. 

Aside  from  their  uses  as  diluents,  the  volatile  oils  are 
powerful  solvents  of  certain  gums  and  resins  of  both 
hard  and  soft  composition.  Varnish  manufacturers  have 
been  most  liberal  purchasers  and  users  of  them  for  that 
purpose,  and  increase  each  year,  as  the  phenomenal 
increase  in  their  output  necessarily  demands  more  and 
more. 


CHAPTER  XX 

VEHICLES  (Continued) 

Varnishes,  Japans,  Alcoholic  Solutions  of  Shellac,  etc. 
VARNISHES 

General  Remarks 

UNDER  the  general  name  of  varnishes,  many  differently 
constituted  liquids  are  to  be  found.  Naturally, 
according  as  to  how  these  are  composed  and  com- 
pounded, they  vary  in  their  characteristics,  each  being 
better  adapted  than  are  the  others  for  some  particular 
line  of  usefulness.  The  term  varnish  seems  applicable 
to  any  liquid  holding  gums  or  gum-resins  in  solution, 
which  upon  the  loss  of  its  volatile  parts,  and  upon 
the  oxidation  and  hardening  of  its  fixed  oil  and 
gum-resins,  shows  a  gloss  upon  surfaces  over  which  they 
are  applied. 

Some  liquids  will  make  a  varnish  (when  properly 
treated)  upon  drying  —  as  linseed  oil  will,  after  it  has 
been  heated  at  a  high  heat  —  but  the  gloss  is  greatly 
improved  by  the  addition  of  gum-resins  of  various 
kinds. 

In  point  of  fact,  no  varnishes  are  made  thus,  and  all  may 
be  said  to  be  composed  chiefly  of  gum-resins;  the  liquids 
used  as  solvents  for  these  may  be  fixed  oils,  volatile  oils 
or  various  mixtures  of  those  two,  or  it  may  be  alcohol  as  in 
the  so-called  spirit  varnishes. 

211 


212  MODERN  PIGMENTS 

Properties  and  Uses 

Varnishes  —  aside  from  the  uses  for  which  they  are 
principally  adapted,  i.e.,  the  finishing  of  surfaces  with 
a  glossy  coating,  over  paint  put  on  in  the  ordinary  way, 
in  graining,  or  over  car,  coach  or  carriage  work,  or  over 
the  natural  wood  itself,  as  in  hard-wood  finishing,  or  in 
enameling  or  japanning  —  they  are  also  used  as  a  vehicle 
for  the  direct  application  of  pigments.  Enamel  painting 
depends  chiefly  upon  their  use  as  pigment  vehicles. 
Iron  bed  manufacturers,  bicycle  factories  and  japanning 
works,  use  them  as  vehicles,  and  they  are  true  vehicles 
in  every  sense  of  the  word,  with  this  difference,  that 
the  fixed  oils  and  their  volatile  adjuncts,  are  so  of  their 
own  selves  —  while  varnishes  are  not,  but  become  so  by 
the  nature  of  their  component  elements,  which,  as  was 
seen,  are  chiefly  of  those  two  classes  of  vehicles  plus  the 
gum-resins  which  also  act  as  binders. 

The  painting  must  necessarily  partake  of  the  nature  of 
its  thinning  varnish  vehicle,  some  kinds  of  painting 
requiring  certain  varieties  of  varnish  for  thinners,  and 
others,  again,  requiring  different  ones. 

The  varnishes  which  contain  linseed  oil  as  their  principal 
solvent  and  which  have  hard  gums  in  their  composition 
—  such  as  gum  copal  —  are  slow  driers,  but  are  elastic, 
and  in  some  degree  resist  the  elements.  Such  are  desig- 
nated for  outdoor  or  exposed  conditions. 

Then  for  inside  work,  varnishes  whose  main  solvent  is 
turpentine  or  the  petroleum  volatile  oils  plus  some  lin- 
seed oil  for  binder,  will  be  preferably  used  for  inside  work, 
as  they  dry  hard,  and  being  protected  from  atmospheric 
changes  and  moisture  they  answer  fairly  well  for  the 
purpose  where  hurry  and  expense  are  to  be  closely 
considered. 


VEHICLES  213 

It  is  not  intended  in  this  work  to  give  varnishes  such 
attention  and  notice  as  would  be  expected  in  a  treatise 
upon  coach  painting,  for  instance,  as  the  only  relation 
in  which  they  are  of  any  interest  in  connection 
with  a  book  upon  pigments  is  as  to  their  use  as  vehicles 
of  them.  As  vehicles,  their  glossy  properties  are 
secondary,  —  in  fact,  of  no  interest  whatever  even  to  the 
coach  painter,  with  the  exception  of  the  enamelers,  who 
do  not  varnish  over  their  wares  afterward. 

To  resume,  then,  in  a  few  words  their  values  as 
vehicles,  the  following  advice  is  given:  For  per- 
manent outdoor  work,  select  some  varnish  made 
from  hard  gum  resin  dissolved  in  linseed  oil;  mainly 
of  this  description  will  be  found  the  wearing  body 
varnishes  of  the  carriage  trade,  and  some  of  the  better 
carriage  parts  varnishes,  and  the  so-called  spar  varnishes 
or  outside  varnishes,  which  are  made  to  withstand 
hardships.  Some  few  of  the  best  grades  of  rubbing 
varnishes  are  also  of  this  order. 

For  work  that  is  not  exposed,  the  better  grades 
of  the  so-called  inside  varnishes  are  made  from 
less  expensive  gum  resins,  and  all  of  softer  texture 
with  a  larger  proportion  of  volatile  oils,  and  will 
answer  fairly  well.  There  is  a  wide  range  between 
the  poorest  and  the  best,  and  one  must  be  governed 
by  the  circumstances  when  selecting  for  certain 
purposes. 

Some  manufacturers  list  varnishes  especially  prepared 
for  mixing  with  colors.  However,  if  one  has  used  a  cer- 
tain quality  of  varnish  with  good  results,  he  should 
hesitate  to  continue  its  use,  as  he  is  likely  to  have 
some  trouble  at  first  with  even  a  good  new  one  with  which 
he  is  unacquainted. 


214  MODERN  PIGMENTS 

JAPANS 

Properties  and  Uses 

It  is  a  very  hard  matter  to  give  a  true  definition  of 
what  is  really  meant  by  the  term  japan,  notwithstanding 
the  daily  use  of  it  in  the  paint  shop. 

It  is  a  varnish,  and  should  be  classed  as  such  and  with 
them.  As  popularly  known  and  understood  by  many 
painters,  it  means  to  them  simply  a  liquid  drier.  To  the 
carriage  trade  and  to  the  color  grinders,  it  means  a  vehicle 
for  the  application  of  paint  and  for  the  grinding  of  it  in  ; 
and  to  the  japanners  and  to  the  enamelers,  a  baking 
varnish.  In  the  last  relation,  it  certainly  is  a  varnish. 

It  is  needless  to  say  that  japans  vary  as  much  in  their 
composition  as  they  do  in  their  qualities,  according  to  the 
formulas  under  which  they  have  been  made,  and  these 
are  legion. 

They  can  be  divided  into  three  classes.  The  first,  which 
the  house  painters  chiefly  use  are  liquid  driers,  and  con- 
sist principally  of  a  solvent  and  some  oxide  of  manganese. 
These  are  not  varnishes  in  any  sense  of  that  word. 

The  second  class,  which  are  for  grinding  and  applying 
coach  colors,  are  properly  varnishes,  and  of  such  are  the 
gold  sizes  and  coach  japans,  and  in  reality  should  be 
classed  among  the  medium  grades  of  varnishes.  They 
make  good  vehicles  for  the  purpose  for  which  they  are 
used.  A  great  variety  of  good,  bad,  and  indifferent  coach 
japans  are  made,  and  the  price  paid  for  them  is  not  always 
an  indication  of  their  quality. 

THIRD  CLASS 

The  varieties  used  in  baking  by  enamelers  are  made 
so  as  to  stand  that  operation.  They  evaporate  under 
heat,  and  soften  sufficiently  to  permit  the  coating  of  paint 


VEHICLES  215 

to  level  up  free  from  brush  marks  and  then  dry  with  a  full 
gloss.  There  can  be  no  doubt  as  to  the  character  of 
these  nor  of  the  japans  used  by  the  radiator  men. 
According  to  the  gums  entering  in  their  composition,  they 
are  either  good  or  bad.  Manufacturers  of  bicycles  and 
enameled  iron  bedsteads,  etc.,  usually  immerse  all  their 
commodities  in  a  dipping  tank  and  stand  them  on  inclined 
drying  boards,  where  the  surplus  color  runs  off,  instead 
of  hand-brushing  the  color. 

These  varnishes  are  probably  called  japan  from  the 
fact  that  all  the  small  articles  of  bric-a-brac  found  on 
the  market  have  a  smooth  finish,  usually  obtained  by 
what  is  known  as  japanning,  by  baking  in  ovens  specially 
constructed  for  the  purpose.  These  articles  are  made  to 
imitate  in  their  finish  the  smooth  lacquering  put  on  the 
same  class  of  ware  imported  from  Japan  and  China. 
The  name,  no  doubt,  was  transferred  and  applied  from 
the  country  to  the  finish,  and  means  that  here.  In  so 
far  it  is  easy  enough  to  understand  how  such  varnishes 
can  be  called  Japan,  but  why  the  same  name  is  used  by 
the  trade  for  mixing  varnishes  of  the  coach  painter  or 
the  liquid  drier  of  the  house  painter  is  one  of  the  conun- 
drums which  life  is  too  short  to  unravel. 

ALCOHOLIC  SOLUTIONS  OF  SHELLAC 

Properties  and  Uses 

Shellac  varnish  as  it  is  sometimes  called,  or  simply 
shellac,  which  to  many  means  the  same  thing,  and  spirits 
shellac,  as  it  is  known  in  the  British  Isles,  are  all  one  and 
the  same  thing.  It  is  simply  shellac,  either  the  orange 
or  the  white,  dissolved  in  alcohol. 

It  makes  a  fair  vehicle  for  pigments,  where  speed  and 
quick  drying  are  imperatively  demanded.  This  varnish, 


216  MODERN  PIGMENTS 

owing  to  the  volatility  of  its  solvent, —  alcohol, —  sets  very 
quickly,  —  in  a  few  minutes, —  and  in  a  few  more  it  is  dry 
and  so  hard  that  the  painting  done  with  it  cannot  be 
brushed  over  without  marring  it. 

Owing  to  its  setting  so  quickly,  it  is  very  hard  to  apply 
properly,  and  it  requires  an  expert  to  handle  it  success- 
fully. Its  use  must  be  confined  to  hurried  work,  and 
for  that  it  has  no  equal. 

The  above  concludes  the  list  of  vehicles  used  in  paint- 
ing,—  at  least  those  worthy  of  consideration. 

There  is  a  possibility  of  some  others  becoming  very 
useful  at  some  future  time,  but  their  cost  is  now  too  great 
to  really  entitle  them  to  notice.  Of  this  class  is  China 
wood  oil  or  Tung  oil,  which  is  said  to  possess  very  good 
qualities.  Should  it  be  possible  to  acclimatize  it  here, 
and  its  cost  brought  somewhere  near  that  of  linseed  oil, 
it  might  prove  a  dangerous  rival;  but  it  has  never  been 
given  the  proper  tests  for  endurance,  etc.,  which  would 
warrant  any  one  forming  more  than  conjectural  opinions 
concerning  its  possibilities. 

Correctives  are  used  with  vehicles,  as  was  intimated; 
and,  again,  some  solids  are  binders  to  add  to  vehicles  con- 
taining no  binding  properties.  The  next  chapter  will  be 
devoted  to  these. 


CHAPTER  XXI 
WAXES 

BEESWAX 

Properties  and  Uses 

WAXES  are  not  used  as  vehicles  in  painting, —  as  are  the 
liquid  vehicles,  —  owing  to  their  property  of  solidifying  in 
a  few  moments,  at  ordinary  temperatures,  as  that  makes 
it  impossible  to  melt  them,  mix  them  with  pigments,  and 
apply  the  paint  so  mixed  before  it  would  have  cooled  and 
become  so  hard  that  nothing  could  be  done  with  them  in 
the  ordinary  way. 

Encaustic  painting,  however,  was  known  and  prac- 
ticed long  before  the  present  system  of  painting  was  so 
much  as  dreamed  of.  The  ancient  civilizations  made  use 
of  it  freely,  and  some  of  the  work  of  their  now  unknown 
artists  is  occasionally  found  in  as  fresh  and  well-preserved 
a  condition  as  when  it  was  first  applied  centuries  ago. 

There  is  still  some  encaustic  work  done,  but  in  an 
amateurish  way,  as  artists  much  prefer  the  use  of  linseed 
oil  to  the  slow  and  difficult  method  of  applying  paint  by 
the  encaustic  process. 

In  encaustic  painting  the  colors  are  first  put  on  with 
a  liquid,  —  water  will  answer  as  well  as  any,  —  and  after- 
ward the  wax  (when  it  has  been  melted  by  heat)  is  flowed 
over  it.  A  flat,  hot  iron  is  used  on  it  to  obtain  a  per- 
fectly level  surface.  The  finish  is  certainly  very  pleasing; 
and  the  colors,  being  hermetically  sealed  from  contact 

217 


218  MODERN  PIGMENTS 

with  air,  are  not  injuriously  acted  upon.  It  stands  to 
reason  that  for  the  finishing  of  interiors  at  least  such 
work  must  be  permanent. 

Beeswax  was  probably  the  form  of  wax  used  in  the 
encaustic  painting  of  the  ancients,  although  they  were 
also  acquainted  with  the  waxes  derived  from  vegetable 
substances. 

Beeswax  is  used  for  many  purposes  by  the  house 
painter, —  in  fact,  all  forms  of  waxes  are, —  not  so  much 
as  a  vehicle  as  it  is  for  the  finishing  of  floors  or  wood- 
work, and  large  quantities  of  it  are  annually  consumed  by 
the  paint  trade. 

As  it  comes  from  the  melting  pots',  it  usually  is  of 
yellow,  but  often  is  found  of  a  brownish  tone;  tlje  latter 
being  impure,  it  must  be  rectified  and  bleached  before  it 
is  fit  for  the  best  work.  The  process  of  bleaching,  also 
raises  its  melting-point  and  hardens  it. 

Beeswax  is  a  vegetable  product  gathered  by  bees  from 
plants,  and  is  not  an  animal  production  as  some  errone- 
.ously  suppose  it  to  be.  It  is  permanent  for  interior 
work,  but  when  exposed  to  the  inclemencies  of  the 
weather  upon  the  outside,  it  is  partially  destroyed  by 
oxidation. 

VEGETABLE  WAXES 

Characteristics 

Many  plants  produce  wax,  and  in  South  America, 
especially  in  Brazil,  it  is  gathered  from  the  leaves  of 
Copernica  cerifera,  where  it  occurs  in  thin  sheets.  It  is 
a  regular  article  of  commerce  in  that  country.  In  China 
and  the  Thibet  there  is  an  extensive  trade  done  in  vege- 
table wax.  Its  melting-point  is  high,  185°  F.  But  for 
its  limited  quantity  and  consequent  high  price,  it  would 


WAXES  219 

be  more  extensively  used  here;  it  makes  a  hard  wax. 
Vegetable  wax  is  used  for  all  purposes  indicated  under 
the  heading  of  beeswax. 

PARAFFIN  WAXES 

Characteristics 

Paraffin  waxes  are  the' product  of  petroleum  distillation 
and  vary  very  much.  Most  of  them  have  such  a  low 
melting-point  as  to  unfit  them  for  encaustic  painting  or 
any  other  purpose  of  the  painter.  Their  melting-point 
ranges  from  105°  to  180°  F.  The  very  highest  qualities 
of  them  are  very  good,  and  in  one  respect  at  least  render 
them  superior  to  the  vegetable  waxes  in  that  they  are 
not  so  readily  acted  upon  by  the  volatile  oils,  nor  will  they 
mix  with  them  as  those  do.  Such  will  consequently 
make  excellent  binders  for  pigments  for  encaustic  work 
or  for  the  waxing  of  floors  where  their  hardness  is  greatly 
in  their  favor.  It  is  also  useful  to  add  to  such  very  heavy 
pigments  as  quicksilver  vermilion,  as  it  helps  to  prevent 
the  separation  and  precipitation  of  that  pigment  when 
mixed  in  linseed  or  poppy-seed  oils,  but  small  quantities 
of  it  should  be  used  for  such  a  purpose. 

While  encaustic  painting  is  commonly  done  by  using 
the  wax  as  a  covering  for  the  colors  previously  applied, 
and  not  as  the  vehicle  to  convey  them  to  the  work,  yet 
there  have  been  some  very  fine  pictures  painted  where 
it  was  used  as  the  vehicle  for  the  mixing  of  the  pigment 
and  of  its  application.  This  requires  great  skill,  and  is 
not  likely  to  ever  become  popular,  as  both  the  work  itself 
must  be  kept  warm  as  well  as  the  vessels  containing 
the  melted  wax  and  pigment. 


CHAPTER  XXII. 

SUBSTANCES  USED  IN  BINDING  PIGMENTS 
GLUES 

General  Remarks 

THE  substances  whose  description  is  attempted  in  this 
chapter  are  not  vehicles  themselves,  being  solid  sub- 
stances, but  are  adjuncts  to  liquid  vehicles  which  do  not 
possess  any  binding  properties  within  themselves  capable 
of  fastening  the  pigments  for  the  application  of  which 
they  serve  as  a  medium  to  surfaces  and  which  other- 
wise through  their  lack  of  adhesiveness  would  fall  down, 
wash  away,  or  blow  off  from  them  upon  on  the  least 
provocation. 

In  distemper  painting,  for  instance,  water  is  the  vehicle 
used,  and  no  arguments  are  necessary  to  show  that  paint 
applied  with  it  would  have  absolutely  nothing  to  hold 
it  after  the  water  had  evaporated.  These  binding  sub- 
stances are  added  to  hold  the  pigments  to  their  place,  and 
they  become  parts  of  the  paint  itself  after  the  vehicle  has 
evaporated. 

Among  the  agents  which  are  principally  used  for  this 
purpose,  glue  easily  holds  first  place,  not  that  it  is  the  best 
of  all,  but  because  it  is  the  most  economical  as  well  as 
the  handiest  of  any  on  the  list.  It  is  by  long  odds  the 
one  binding  substance  which  is  most  universally  used, 
and  the  quantity  annually  employed  for  the  purpose  is 
something  enormous. 

220 


SUBSTANCES  USED  IN  BINDING  PIGMENTS      221 

It  is  not  only  employed  by  painters  in  the  preparation 
at  the  home  shop  of  distemper  colors,  but  the  numerous 
concerns  which  have  sprung  up  within  the  past  twenty- 
five  years  with  ready-prepared  water  paints  or  kalsomines 
or  anti-kalsomines  of  all  sorts,  prepared  from  gypsum, 
etc.,  —  which  are  all  ready  for  use  by  the  simple  addition 
of  either  hot  or  cold  water, —  these  use  incredible  quan- 
tities of  it  in  the  compounding  of  said  ready-prepared 
distemper  paints.  This  preparation  of  wall  water-paints 
has  grown  up  into  a  great  industry  and  is  extended  every 
year,  and  they  are  found  for  sale  in  every  general  store  in 
the  land.  They  are  uniform,  handy  to  use,  and  usually  give 
better  satisfaction  than  that  which  the  average  painter 
is  able  to  prepare  for  himself.  The  above  is  not  said  in 
order  to  discourage  any  one  from  mixing  his  own  com- 
pounds, but  as  a  statement  of  fact.  There  is  no  doubt 
but  that  any  intelligent  painter  can  mix  a  batch  of  dis- 
temper colors  just  as  they  ought  to  be;  but  although 
this  is  simply  done,  it  must  be  done  just  right.  In  the 
hurry,  which  is  usually  the  condition  existing  during  the 
busy  season  of  the  spring,  trifles  are  forgotten  or  dis- 
carded for  want  of  time.  Many  a  painter  who  has  been 
too  busy  to  properly  prepare  a  batch  of  distemper  color 
to  be  sent  out  on  a  job,  sees  it  go  out  of  the  shop  door 
with  misgivings  as  to  its  future.  Many  an  eyesore  and 
heartache  might  have  been  avoided  by  the  use  of  a  well- 
prepared  water  paint  which  could  have  been  sent  out  to 
a  job  without  loss  of  time  and  saved  a  good  bit  of  worry. 

Properties  and  Uses 

Glue  is  an  animal  product,  obtained  by  the  boiling  of 
hoofs,  bones,  cartilaginous  parts  of  carcasses,  hides,  hide 
trimmings  from  the  tanneries,  and  even  parts  of  flesh. 
If  the  treatment  is  done  at  a  temperature  above  the 


222  MODERN  PIGMENTS 

ordinary  boiling  heat,  the  process  is  greatly  hastened. 
The  various  processes  and  manipulations  are  all  simple 
and  well  known,  but  too  lengthy  to  give,  and  can  be 
summarized  thus:  Glue  is  the  residue  which  remains  by 
boiling  the  animal  parts  referred  to  and  afterward  drying 
the  same  when  it  has  been  cleansed  of  impurities  by 
various  processes  of  clarification,  etc. 

Its  binding  properties  are  due  to  two  distinct  yet 
similar  compounds,  gelatin  and  chondrin.  The  chemical 
composition  of  those  bodies  is  carbon,  hydrogen,  nitrogen, 
and  oxygen  in  various  combinations.  Both  substances 
are  entirely  soluble  in  hot  water  and  are  coagulated  by 
tannin.  Cold  will  also  coagulate  them,  hence  the  well- 
known  property  which  is  exhibited  every  time  one  mixes 
a  pail  of  kalsomine, — it  "jells"  when  it  cools,  which  makes 
it  work  smoother  and  makes  it  easier  applied  than  before 
coagulating. 

Glues  are  thrown  in  three  different  classes,  according 
to  the  material  that  was  used  in  their  preparation. 

1st.  Hide  glue,  made  from  skins,  ears,  tendons,  hide 
trimmings  from  the  tanyards,  and  similar  offal. 

2d.  Bone  glue,  from  hoofs,  feet,  bones,  joints,  and  any 
osseous  offal. 

3d.  Fish  glue,  made  from  the  bladders,  entrails, 
scales,  and  bones  of  fish. 

All  are  well  aware  of  the  great  difference  in  the  strength 
possessed  by  various  glues.  This  depends  upon  the 
material  of  which  they  have  been  made,  and  in  a  lesser 
degree  upon  the  manner  of  their  preparation. 

Hide  glues  are  the  strongest  of  any,  and  possess  the 
greatest  tenacity.  Bone  glues  are  the  weakest.  It  is 
difficult  to  make  a  glue  salesman  own  up  that  any 
of  his  samples  are  bone  glue,  but  some  of  them  certainly 
are.  Fish  glue,  especially  that  made  from  Russian  stur- 


SUBSTANCES  USED  IN  BINDING  PIGMENTS     223 

geon  stock,  is  very  strong.  Some  of  the  fish  glues  made 
from  the  bladders  are  not  only  very  strong,  but  as  clear 
as  glass,  offering  no  obstacle  whatever  to  the  passage  of 
light  rays,  —  any  more  than  would  so  much  crystal.  Isin- 
glass is  only  a  very  fine  form  of  such  fish  glue.  The 
bone  glues  usually  furnish  that  form  of  glue  known 
as  gelatin. 

Glues  range  in  color  from  that  which  is  light  and  trans- 
parent to  the  dark  brown  stinking  refuse,  which  forcibly 
reminds  one  of  being  very  near  a  spot  where  animal 
matter  is  decaying. 

That  which  is  prepared  for  the  binding  of  kalsomine  or 
water  colors  is  known  to  the  trade  as  kalsomine  glue.  In 
shape  it  is  in  thin  sheets,  which  are  broken  up  in  small 
pieces  before  packing  in  barrels.  There  are  many  quali- 
ties of  it.  That  which  breaks  with  an  elastic  fracture 
and  is  of  a  light  creamy  tone  is  usually  good.  If  it 
is  very  white  and  opaque,  the  chances  are  that  it 
has  been  weighted  with  some  adulterating  sub- 
stance. These  white  weighted  glues  are  not  as 
economical  nor  as  satisfactory  as  those  of  a  creamy 
semi-transparent  tone. 

Glue  comes  also  in  a  pulverized  form,  ground  up  in 
small,  angularly  shaped  particles,  and  it  is  to  be  found  thus 
in  all  grades  from  poor  to  good.  Usually  ^these  do  not 
run  as  strong  as  the  regular  kalsomine  glues  do,  but  the 
better  qualities  answer  the  purpose  well  enough.  The 
ground  glues  dissolve  more  readily  than  those  that  have 
not  been  broken  up,  and  the  thin  ones  of  the  kalsomine 
glue  sorts  dissolve  quicker  than  the  thick  glues.  Glue, 
however,  of  any  and  all  shapes,  can  be  used  for  the  pur- 
pose of  binding  pigments  in  distemper  work.  It  is  only 
a  question  of  convenience,  saving  of  time,  and  of  a  knowl- 
edge of  the  strength  that  they  possess,  as  without  that 


224  MODERN  PIGMENTS 

it  will  be  impossible  to  properly  gauge  the  proper  quan- 
tity of  it  to  use  for  the  binding  of  a  given  weight  of  pig- 
ment. Glue  has  the  property  of  absorbing  moisture  and 
of  retaining  it  when  it  comes  in  contact  with  cold  water, 
but  it  is  not  dissolved  by  it.  This  well-known  pecul- 
iarity is  made  use  of  by  painters  to  hasten  its  solubility 
and  to  melt  it.  The  glue  is  soaked  in  cold  water  over 
night.  During  that  period,  it  will  have  absorbed  several 
times  its  own  weight  of  that  liquid.  It  will  then  be 
swollen  much  above  its  normal  bulk  and  softened  in 
texture.  This  soaked  and  swollen  glue,  when  placed  in 
a  vessel  over  the  stove,  will  readily  dissolve  at  a  low  heat, 
and  thus  will  save  much  time  and  worry  in  melting  it  in 
the  dry  state,  as  then  it  requires  constant  stirring  and 
much  more  heat  besides  care,  or  it  will  burn  at  the  bottom 
of  the  vessel.  When  melted,  it  is  ready  to  mix  with  the 
pigments,  which  should  always  be  done  before  it  has  had 
time  to  cool  and  become  jellied. 

In  warm  weather,  putrefaction  commences  early  in 
colors  thus  prepared,  and  unless  one  has  a  refrigerator 
for  the  surplus  that  cannot  be  used  the  same  day,  it  will 
be  better  and  pleasanter  to  mix  no  more  than  will  be  used 
up  clean  that  day. 

To  lessen  the  tendency  to  putrefaction,  a  few  drops  of 
carbolic  acid  or  eugenol  (oil  of  cloves)  may  be  added. 
This  will  retard  fermentation,  but  will  not  prevent  it. 

GUM  ARABIC 

Properties  and  Uses 

Gum  arabic  is  probably  the  best  binding  substance 
known  for  water  colors,  and  if  it  is  given  only  second 
place  on  the  list,  it  is  not  because  it  does  not  deserve  to 
have  the  first,  but  because  its  much  greater  cost  and 


SUBSTANCES  USED  IN  BINDING  PIGMENTS      225 

also  the  greater  care  and  difficulty  in  its  use  render 
its  universal  employment  impossible;  and  also  on  ac- 
count of  another  reason:  if  gum  arabic  was  used  to 
the  same  extent  as  glue  is  for  binding  pigments,  there 
would  not  be  enough  of  it  in  the  market,  and  its 
cost  would  soar  so  high  as  to  put  it  out  of  commission 
at  once. 

Gum  arabic  is  a  true  gum,  and  consequently  it  is  of 
vegetable  origin.  It  is  produced  from  several  species  of 
acacia.  That  best  known  is  supposed  to  be  produced 
from  Acacia  Arabica,  and  its  name  is  derived  from  that; 
but  in  reality  it  is  derived  from  Acacia  Senegal,  which  is 
much  more  common,  and  the  gum  arabic  of  commerce  is 
chiefly  obtained  from  that  variety. 

Its  composition  is  a  mixture  of  the  salts  of  arabic  acid, 
these  salts  being  of  three  bases,  —  potash,  lime,  and  mag- 
nesia with  water. 

The  better  specimens  are  nearly  all  free  from  color, 
clear,  and  nearly  if  not  wholly  soluble  in  water,  and  the 
solution  clear. 

Gum  arabic  dissolves  very  slowly  in  cold  water;  boiling 
water  must  be  used  in  making  solutions.  It  should  be 
pulverized  to  facilitate  this,  as  it  takes  a  long  time  to  dis- 
solve the  lumps.  After  the  solution  is  made,  it  should 
stand  for  a  day,  and  the  clear  liquid  poured  off,  when  the 
undissolved  impurities  will  be  found  at  the  bottom  and 
should  be  left  undisturbed.  It  should  be  prepared  before- 
hand, so  as  to  have  it  at  a  moment's  notice.  It  will  be 
well  to  guard  against  any  fermentation  by  the  addition 
of  a  few  drops  of  eugenol  or  of  a  lump  of  camphor 
which  will  float  upon  the  top;  this  will  prevent  it  from 
souring. 

Being  so  much  more  slowly  acted  upon  by  cold  water 
than  the  glues,  and  being  so  much  less  subject  to  putre- 


226  MODERN  PIGMENTS 

faction  than  animal  matter,  its  use  is  indicated  for  dis- 
temper, fresco,  and  all  good  water-color  work.  For 
artists'  use  in  water  colors,  it  is  indispensable. 

The  above  two  substances,  i.e.,  glues  and  gum  arabic, 
are  the  two  most  important  substances  as  binding  agents 
for  distemper  colors.  There  are  a  few  other  substances 
used,  but  to  so  limited  an  extent  as  to  deserve  little 
more  than  passing  mention. 

These  have  been  grouped  below,  and  consist  of  starch, 
dextrin,  honey,  molasses,  sugar,  and  glycerine. 

STARCH 

Properties  and  Uses 

Starch  is  a  substance  well  known  to  everybody, 
and  is  derived  from  the  cereals  and  the  bulbous  roots 
of  plants,  as  potatoes,  yams,  etc.  Starch  mixed 
with  cold  water  into  a  stiff  paste,  and  in  which 
hot  boiling  water  has  been  poured  until  it  has  become 
stiff  and  unctuous,  has  been  and  is  occasionally 
used  to  mix  pigments  and  apply  them  to  surfaces. 
Its  use  for  such  a  purpose  can  only  be  tolerated  upon 
the  plea  of  dire  necessity,  when  no  other  and  better 
binders  are  procurable,  and  cannot  be  recommended 
even  for  the  cheapest  kind  of  work. 

DEXTRIN 

Properties  and  Uses 

The  Dextrin  of  commerce  is  derived  from  starch.  While 
its  adhesiveness  is  greater  than  that  substance,  it  is  so 
much  weaker  than  that  of  either  glue  or  gum  arabic, 
that  its  use  is  very  questionable  as  a  binder  for  distemper 
painting.  It  has  another  fault,  in  that  it  softens  in  warm 


SUBSTANCES  USED  IN  BINDING  PIGMENTS      227 

weather;  and  those  who  have  had  to  do  with  sticky  enve- 
lopes and  stuck-together  stamps  will  know  enough  not 
to  want  to  fool  with  it. 

As  a  corrective,  used  in  small  quantities  with  glues,  it 
is  said  that  it  will  prevent  the  suction  of  hot  walls  and 
keep  the  color  from  striking  in  too  rapidly. 

HONEY,  SUGAR,  AND  MOLASSES 

Properties  and  Uses 

Honey,  from  its  soft  condition  at  all  times,  is  not  fitted 
for  the  binding  of  colors;  molasses  is  similarly  constituted; 
while  sugar  is  a  solid  which  by  the  addition  of  water  can 
be  brought  to  the  consistency  of  syrup.  The  three 
possess  about  the  same  properties,  and  are  too  weak  for 
the  binding  of  water  colors.  As  correctives  to  be  used 
with  distemper  colors  mixed  with  glue,  they  are  fre- 
quently resorted  to  for  the  same  purposes  as  mentioned 
under  the  heading  of  dextrin.  Honey  is  also  used  as  a 
corrective  in  the  preparation  of  artists'  water  colors  in 
the  form  in  which  they  are  so  popular  now,  that  of  moist 
pans.  It  is  also  used  in  very  limited  quantity  in  the 
hard  cakes  to  prevent  the  gum  arabic  in  their  compound- 
ing from  becoming  too  brittle  and  crumbling  to  pieces. 
As  honey  usually  becomes  crystalline,  and  in  that  condi- 
tion is  as  useless  as  granulated  sugar  would  be,  it  is 
treated  to  prevent  its  crystallization,  and  has  its 
dextrose  removed.  This  is  accomplished  by  mixing 
it  with  four  times  its  bulk  of  alcohol  and  keeping  it 
agitated  every  few  hours  for  two  consecutive  days; 
then  the  pale  alcoholic  solution  is  filtered.  It  is 
fit  to  use  in  that  condition,  or  the  alcohol  may  be 
recovered  by  distillation,  and  the  residue  in  a  syrupy 
condition  may  be  used  instead. 


228  MODERN  PIGMENTS 

GLYCERINE 

Properties  and  Uses 

Glycerine  is  obtained  from  oils  and  fats.  Many  of  the 
large  soap  works  produce  it  as  a  by-product.  It  is  of  the 
consistency  of  a  thin  syrup  and  has  a  sweetish  taste.  It 
attracts  moisture  readily,  and  will  absorb  more  than  one 
third  of  its  weight  from  the  atmosphere.  That  which  is 
found  in  commerce  has  always  some  water  in  its  com- 
position. This  can  be  readily  detected  by  its  specific 
gravity  and  the  percentage  of  water  computed  from  the 
variation  of  that  which  it  shows  and  that  which  it  ought 
to  have.  Its  great  attraction  for  water  really  makes  it 
superior  to  honey  in  the  manufacture  of  cake  and  moist 
cake  water  colors,  and  many  are  beginning  to  use  it  for 
that  purpose. 

It  is  also  very  useful  to  add  to  distemper  colors  and 
kalsomine  for  wall-work  and  for  rooms  where  the  plas- 
tering is  in  that  condition  which  is  known  as  hot.  It  will 
greatly  facilitate  the  application  of  the  paint  into  which 
it  has  been  added  in  the  proportion  of  four  to  six  fluid 
ounces  to  the  pail  of  color  (about  2J  gallons).  Its  use 
has  saved  many  a  man  from  profanity. 


CHAPTER  XXIII 

DRIERS  AND  SICCATIVES 

General  Remarks 

It  has  been  noted  in  the  descriptions  of  the  various 
pigments  that  some  of  them  were  called  non-driers. 
The  pigments  themselves,  being  powdered  solids,  never  dry 
any  more  than  they  do  when  ground  up  with  oil  to  a 
paste.  The  term,  therefore,  does  not  apply  to  them 
really,  but  to  the  linseed-oil  vehicle  with  which  they  are 
mixed,  and  refers  to  the  action  of  the  pigment  upon  the 
oil.  It  was  also  noted  that  some  other  pigments  on  the 
contrary  aided  the  drying  of  the  fixed  oils. 

The  main  reason  for  the  non-drying  of  pigments  is  that 
some  contain  fatty  oils  which  do  not  dry;  there  are  also 
other  reasons  which  were  noted  under  each  head.  Again, 
it  was  noticed  that  the  lead  pigments  which  were 
oxides  of  that  metal,  and  that  pigments  also  which  con- 
tained oxide  of  manganese  in  their  composition,  hastened 
the  drying  of  the  oils. 

The  oxides  of  lead  are  all  very  good  driers,  but  also 
some  of  the  other  salts  of  that  metal  and  acetate  of  lead 
are  especially  so;  even  white  lead  itself  possesses  that 
property  to  a  good  degree  but  not  in  such  proportion 
as  some  others.  It  will  usually  dry  raw  linseed  oil  in  a  few 
hours  outside,  without  the  addition  of  artificial  driers 
unless  the  weather  is  cold  and  the  atmosphere  too  humid. 

In  describing  the  drying  of  linseed  oil,  it  was  said  that 
the  heating  of  the  linseed  oil  of  itself  rendered  it  more 

229 


230  MODERN  PIGMENTS 

siccative,  so  that  even  subsequently,  after  it  had  cooled, 
it  would  still  retain  some  of  its  thus  acquired  drying 
quality. 

Linseed  oil  would  dry  naturally  when  mixed  with  inert 
pigments,  as  these  exert  no  influence  upon  its  drying  one 
way  or  another;  and  with  the  pigments,  which  will  aid 
its  oxidation  the  more  quickly,  as  these  part  with  their 
oxide  more  rapidly  or  liberally,  and  when  mixed  with  the 
non-drying  pigments  much  more  slowly  or  not  at  all, 
according  to  the  composition  of  the  non-drying  colors. 
If  the  temperature  could  be  depended  upon  to  remain 
above  70°  F.,  and  the  barometer  at  "Beau  Fixe," 
and  only  pigments  mixed  with  linseed  oil  which 
were  not  inimical  to  its  natural  drying,  there  would  be 
but  little  need  of  driers;  but,  unfortunately,  there  can  be 
no  dependence  placed  upon  it.  Neither  the  thermometer 
nor  the  barometer  ever  remain  very  long  where  the 
painter  would  like  them  to  be,  being  proverbially  fickle, 
so,  by  the  use  of  dryers,  he  must  guard  against  the 
possibility  of  having  his  work  destroyed  by  changes  which 
are  likely  to  come  at  a  moment's  notice. 

Again,  in  interior  work,  the  women  folk  are  ever  hurry- 
ing up  the  poor  painter,  and  ever  threatening  all  sorts  of 
evil  to  him,  even  to  threatening  him  that  this  is  to  be  the 
last  job  for  him  there,  if  he  does  not  put  in  a  little  more 
push  to  his  hastening  along  with  it,  when  he  is  doing  all 
that  possibly  can  be  done,  and  more,  for  the  real  good  of 
the  painting;  or  in  business  houses  or  stores,  where  the 
painting  has  to  be  done  at  night,  so  the  paint  may  be 
dry  in  the  morning,  there  is  no  other  alternative  left  to 
the  painter  but  that  of  using  siccatives  in  his  paints,  no 
matter  whether  this  is  good  for  it  or  not. 

There  is  no  doubt  but  that  much  of  the  short  life  of 
paint  complained  of  is  due,  in  part  at  least,  to  the  hurried 


DRIERS  AND  SICCATIVES  231 

drying  of  linseed  oil,  which  burns  it  up  —  that  is  what  fast 
drying  means.  Where  the  drying  is  slow  and  natural, 
the  conversion  occurs  without  violence.  Then  the  paint 
will  stay  on  much  longer  and  remain  in  good  condition 
without  checking  all  over  from  lack  of  adhesion  and 
elasticity. 

BOILED  LINSEED  OIL 

This  is  the  simplest  of  the  siccatives.  The  heating  of 
linseed  oil  renders  it  more  drying.  Boiled  oil,  when  the 
boiling  has  been  done,  as  it  usually  is,  with  the  oxides  of 
lead  or  manganese  present  during  the  process,  renders  it 
still  more  drying. 

How  those  substances  are  capable  of  imparting  oxygen 
to  linseed  oil  without  losing  any  of  it  themselves  is  not 
well  understood.  One  thing  is  sure,  if  a  given  weight 
of  those  oxides  be  placed  in  a  bag  with  the  oil  and  all 
boiled  together,  these  bags  may  be  taken  out  and  the 
linseed  oil  carefully  washed  away  with  benzine,  and  the 
oxide  powders  dried  and  weighed,  when  it  will  be  found 
that  they  have  not  lost  any  of  it  by  the  operation,  but 
the  linseed  oil  will  have  absorbed  oxygen  through  their 
agency  some  way. 

As  a  siccative,  boiled  oil  has  its  uses  even  for  outside 
painting,  but  it  is  seldom  used  for  that  purpose,  probably 
because  the  specially  prepared  liquid  driers  or  japans 
are  more  powerful  siccatives  and  smaller  proportions  are 
necessary  to  accomplish  the  purpose  of  drying  the  oil. 

LIQUID  DRIERS 

General  Remarks 

Manufacturers  of  varnishes  usually  prepare  siccative 
compounds  for  the  drying  of  linseed  oil.  They  are  sold 


232  MODERN  PIGMENTS 

under  many  names,  such  as  drying  japans,  liquid  driers, 
liquid  siccatives,  and  many  fancy  proprietary  names. 

The  solving  medium  used  in  their  preparation  is  really 
of  little  moment,  whether  it  be  linseed  oil,  spirits  of 
turpentine,  naphtha,  benzine,  or  mixtures  of  these.  The 
quantity  necessary  to  dry  a  given  amount  of  linseed  oil 
is  so  small  that  their  presence  in  the  oil  can  exert  little 
influence  other  than  that  which  is  expected  of  them  — 
the  drying  of  the  oil.  An  undue  quantity  added  to  lin- 
seed oil  will  injure  it,  but  then  that  would  happen  no 
matter  what  the  solvent  might  be. 

LEAD  OXIDES 

The  action  of  these  has  already  been  noted,  as,  for 
instance,  when  boiled  with  linseed  oil,  etc.  All  lead 
siccatives  have  one  drawback  that  they  all  hold  in  com- 
mon, they  subject  the  oil,  or  rather  the  pigments  mixed 
with  it,  to  the  action  of  sulphuretted  hydrogen. 

This  is  not  so  noticeable  in  the  liquid  driers  as  it  is 
in  the  paste  driers,  when  the  lead  oxides  themselves 
become  a  part  of  the  paint. 

The  paste  driers  will  be  noted  further  on  more  fully. 

Liquid  driers  are  very  seldom,  if  ever,  made  from  the 
lead  oxides,  for  the  very  good  reason  that  the 

OXIDES  OF  MANGANESE 

are  much  better  adapted  for  that  purpose.  When  made 
with  these,  there  is  no  danger  of  any  further  discolora- 
tion taking  place,  outside  of  that  which  is  produced 
immediately  after  the  mixing  of  the  liquid  manganese 
drier  with  the  paint.  The  greatest  drawback  is  their 
dark  brown  color.  If,  however,  the  brown  borate  of 
manganese  is  used  in  the  preparing  of  the  liquid  drier, 
the  dark  tone  of  the  drier  will  be  reduced  to  a  minimum, 


DRIERS  AND  SICCATIVES  233 

The  manganese  driers  are  such  strong  driers  that,  if 
they  have  been  well  prepared,  but  little  of  them  need  be 
used,  and  that  little  will  influence  the  drying  of  linseed 
oil  a  long  way. 

There  is  absolutely  no  excuse  for  using  the  large  quan- 
tities of  liquid  manganese  driers  many  painters  do.  It 
then  becomes  dangerous,  for  it  burns  the  paint,  and,  in 
excessive  quantities,  it  will  defeat  the  purpose  for  which 
it  is  used  at  all  —  the  drying  of  the  oil.  When  will  the 
careless  painter  learn  that  a  little  manganese  drier  will 
accomplish  the  object  of  drying  oil  much  better  than  the 
larger  quantities  of  it.  Strange  as  the  above  may  sound, 
it  is  not  the  quantity  used  that  causes  the  oil  to  dry 
faster,  for  it  will  take  it  up  only  as  it  needs  it  —  at  its 
convenience,  nor  will  it  take  up  more  than  the  needed 
amount.  Another  strange  fact,  hard  to  explain,  is  that 
when  excessive  quantities  are  used  the  very  object  of 
quick  drying  is  defeated,  as  then  it  seems  rather  to  pre- 
vent than  accelerate  it.  One  large  tablespoonful  of  a 
well-made  standard  average  strength  liquid  drier  is 
amply  sufficient  for  any  ordinary  pail  holding  three 
quarts  of  paint  ready  thinned  for  application.  This  will 
dry  all  ordinary  mixtures  where  white  lead  is  the  base 
of  the  paint.  For  Vandyke  browrn  and  lamp  black,  half 
a  pint  to  the  gallon  of  linseed  oil  will  be  found  suffi- 
cient —  those  two  pigments  being  the  most  anti-drying 
ones  on  the  list. 

PASTE  DRIERS 

The  oxides  of  lead,  we  have  already  seen,  affect  white 
lead  compound  and  others  even  more,  which  are  not 
affected  by  sulphuretted -hydro  gen  gases,  which,  when 
they  are  used,  are  affected  by  their  presence. 

Formerly  large  quantities  of  acetate  of  lead  paste 
driers  were  manufactured,  but  their  defects  under 


234  MODERN  PIGMENTS 

unfavorable  conditions  —  specking  and  coming  out  as  an 
efflorescence  —  have  greatly  reduced  their  use.  Under 
that  form  and  style  they  are  still  used  in  certain  localities. 

Paste  fillers  are  made  and  prepared  according  to  pro- 
prietary formulas,  so  that  what  might  be  a  good  one 
made  by  one  firm  will  not  necessarily  need  to  be  a  recom- 
mendation for  some  one  else's  make,  simply  because  it 
is  put  up  in  that  form.  Acetate  of  lead  is  the  base  of  all 
light-toned  ones.  They  are  used  for  very  light  tints  and 
whites.  Many  an  artist  has  had  to  rue  the  day  when  he 
was  tempted  to  use  them,  as  they  are  chiefly  composed,  as 
was  said,  of  acetate  of  lead,  or  may  also  contain  white 
oxide  of  lead  or  litharge,  which,  however,  darkens  it  some. 
Aside  from  subjecting  the  painting  to  the  action  of  sul- 
phurous vapors,  deteriorating  and  specking  or  efflores- 
cing, there  are  other  injurious  chemical  changes  affecting 
them. 

Sulphate  of  zinc  drier  in  paste  form  is  a  fair  drier  for 
zinc  white,  but  of  little  value  when  used  in  connection 
with  any  other  pigment. 

Borate  of  lime  and  borate  of  zinc  also  make  useful 
driers  for  zinc  paint. 

Some  paste  driers  are  now  made  with  borate  of  man- 
ganese as  the  chief  ingredient  in  their  composition.  Such 
will  be  found  more  effective  and  more  valuable,  even  if 
they  are  a  trifle  dark,  than  the  other  varieties  of  paste 
driers,  but  they  are  not  as  advantageous  as  the  liquid 
driers.  They  require  to  be  carefully  thinned  out  before 
mixing  with  the  paint,  and  for  that  reason  will  never 
become  popular.  It  is  a  waste  of  time  to  triturate  them 
and  thin  them  for  use,  which,  when  done,  puts  them  in 
liquid  form  and  makes  a  liquid  drier  of  them  after 
all.  Why  not  procure  that  in  the  first  place  and  save 
all  the  bother? 


CHAPTER  XXIV 
THE  COMPOUNDING  OF  PIGMENTS. 

THE  compounding  of  pigments  changes  the  color  of 
each,  imparting  to  the  others  a  part,  and  in  return  receiv- 
ing a  part  of  theirs,  so  that  the  completed  mixture  becomes 
a  new  color  different  from  that  of  the  pigments  produc- 
ing it,  but  which  partakes  of  the  character  of  each  one 
of  them  in  some  degree. 

THE  PRIMARY  COLORS 

Of  colors  proper  there  are  but  three.  These  three  are 
called  the  primary  colors.  They  are  the  following: 

Red,   Yellow  and  Blue 

White  itself  is  but  the  product  of  a  perfect  combination 
of  the  three  primaries,  black  being  simply  a  negative  of 
all  color. 

SECONDARY  COLORS 

From  the  combination  of  two  of  any  of  the  primary 
colors  together  are  made  the  secondary  colors,  and  these 
are  as  follows: 

Purple,  Orange  and  Green 

They  are  thus  produced: 

Red  and  blue      =  Purple. 

Red  and  yellow  =  Orange. 

Yellow  and  blue  =  Green. 

235 


236  MODERN  PIGMENTS 

TERTIARY  COLORS 

From  the  union  of  two  of  the  secondary  colors  comes 
a  third  set,  the  tertiary  colors  which  consist  of  the 
following: 

Olive,  Citrine  and  Russet 

They  are  derived  in  this  way: 

Purple  and  green    =  Olive. 
Green  and  orange   =  Citrine. 
Purple  and  orange  =  Russet. 

Further  mixtures  of  these  produce  the  neutral  tints. 

From  the  above  three  primaries,  three  secondaries  and 
three  tertiaries,  with  the  addition  of  white  and  black, 
are  produced  the  hundreds  of  thousands  of  varied  tints 
which  form  the  kaleidoscope  of  infinite  variety  adorning 
everything  animate  and  inanimate  upon  this  mundane 
sphere. 

It  is  regrettable  that  no  more  space  can  be  devoted  to 
the  study  and  notice  of  color  harmony,  but  this  would 
unduly  enlarge  the  volume,  and  it  is  not  strictly  within 
the  subject  matter.  The  color  student  is  therefore  advised 
to  procure  some  of  the  excellent  treatises  which  deal 
with  this  subject  as  their  primary  object.  There  is 
nothing  more  interesting  than  the  study  of  the  phenom- 
ena of  color.  It  will  greatly  help  the  student,  not  alone 
in  that  it  will  help  him  to  mix  tints  properly,  but  also  in 
the  higher  object  of  becoming  master  of  color  effects, 
which  is  a  faculty  that  few  otherwise  very  good  painters 
possess,  and  which  would  be  worth  to  them  in  after  life 
many  times  over  whatever  effort  in  time  and  money  they 
may  have  spent  in  acquiring  a  good  knowledge  of  color. 

Expert  colorists  are  in  good  demand  at  any  reasonable 
figures  which  they. may  demand  for  their  services. 


THE  COMPOUNDING  OF  PIGMENTS  237 

For  the  making  of  tints,  a  base  is  used  upon  which  to 
build  it.  The  base  is  that  pigment  which  enters  the  com- 
pound in  the  greatest  quantity.  If  a  white,  —  and  that 
is  usually  the  base  of  all  light  tints,  —  it  is  either  white 
lead  or.  zinc  white,  used  alone  or  together  in  any  propor- 
tions, and  still  other  whites  may  be  added  to  them  as 
correctives  if  desired. 

The  rules  given  below  are  formulated  for  guidance  in 
the  preparation  of  tints,  with  linseed  oil  as  the  vehicle, 
and  for  pigments  which  have  been  ground  to  a  paste 
in  the  same  vehicle.  These  same  rules  will  apply  to  the 
mixing  of  pigments  and  the  making  of  tints  from  them 
in  any  other  vehicle,  japan,  varnish  or  water,  with  what- 
ever slight  alterations  made  necessary  by  the  different 
nature  of  those  liquids. 

1.   THE  BASE 

The  base,  as  was  said  before,  is  the  principal  color  of 
the  tint.  Tints  usually,  but  not  always,  are  lighter 
tones  of  those  of  the  pigments  used  in  compounding 
them,  so  white  must  be  used  -to  lighten  them  up.  It 
thus  becomes  the  principal  color  or  the  base  upon  which 
the  tint  is  built.  It  may  be  any  white  pigment,  or 
combination  of  them;  but  to  simplify  matters,  and  also 
on  account  of  its  being  the  pigment  in  chief  use  for  the 
purpose,  when  a  white  base  is  designated  hereafter  it 
it  will  be  called  white  lead,  no  matter  if  it  is  that  or  any 
other  white  that  one  may  prefer  to  use. 

In  some  few  cases,  however,  where  great  purity  of 
tone  is  necessary,  and  for  certain  kinds  of  interior  work, 
zinc  white  should  be  substituted.  With  these  explan- 
ations one  cannot  greatly  err.  It  will  be  an  easy  matter 
to  substitute  zinc  for  lead,  when  it  is  well  understood 
that  the  white  lead  base  that  is  indicated  in  the  next 


238  MODERN  PIGMENTS 

chapter  does  not  stand  as  meaning  that  especially,  but 
only  a  white  base  as  the  predominating  pigment. 

The  white  lead  or  zinc  white  or  other  accessory  whites 
must  have  been  broken  up,  as  is  called  the  operation  of 
taking  it  out  of  its  original  package  or  keg  in  which  it 
was  placed  at  the  factory  —  and  thinning  it  with  sufficient 
linseed  oil  to  make  a  rather  stiff  and  smooth  paste.  It  is 
not  such  an  easy  matter  as  it  may  look,  to  a  novice,  to  stir 
up  the  lead  and  to  get  it  into  a  smooth  uniform  mass 
free  from  lumps.  It  is  simple,  but  it  means  hard  work, 
requiring  strength  and  effort  to  perform  it  properly. 
Some  use  a  little  turpentine  with  the  oil,  to  make  it  break 
up  readily,  and  the  small  quantity  required  will  not 
harm  it  for  any  purpose  of  outside  painting.  If  possible, 
the  breaking  up  should  be  done  the  day  before  prepar- 
ing the  tints;  if  left  over  night  many  of  the  small  lumps, 
which  seem  to  defy  the  paddle  and  constantly  escape  it, 
and  which  are  a  cause  of  mental  irritation,  and  thereby 
of  profanity,  become  soaked  up  by  the  linseed  oil  when 
left  in  contact  with  it  over  night,  and  the  next  day  the 
mass  is  more  easily  brought  to  a  uniform  smooth  paste. 
The  tub  or  tubs  used  for  the  breaking  up  of  the  lead 
should  always  be  ready  to  furnish  the  base  in  just  the 
shape  described,  as  it  will  be  found  much  better  than 
freshly  broken  up  lead  for  the  purpose  of  preparing 
tints.  Of  course,  it  is  not  absolutely  necessary  that  it 
should  be  broken  up  ahead  of  the  time  it  is  needed,  but 
it  will  be  found  better,  and  the  better  way  is  what  the 
author  is  trying  to  inculcate. 

2.  THE  COLORING  PIGMENTS 

These,  too,  should  have  been  previously  broken  up  by 
the  gradual  addition  of  small  quantities  of  linseed  oil. 
When  the  pigment  has  been  beaten  up  with  the  oil,  and 


THE  COMPOUNDING  OF  PIGMENTS  239 

has  absorbed  all  the  oil,  forming  a  smooth  paste  of  uniform 
texture,  more  is  added  and  triturated  with  it,  till  again 
that  is  absorbed,  and  a  liquid  is  obtained  which  pours  out 
easily  —  as  thin  as  one  would  wish  to  apply  with  a  brush. 
It  is  only  when  in  this  condition  that  the  coloring  pig- 
ments can  be  added  to  the  base  safely,  as  otherwise  they 
will  not  incorporate  with  it  with  anything  like  uniformity, 
and  the  tint  may  be  streaky,  which  is  an  abomination 
and  a  sure  sign  of  the  incompetency  of  the  tint  mixer. 

3.   MIXING  THE  TINTS 

The  pigments  must  be  added  slowly  to  the  base,  so  as 
not  to  overshoot  the  intended  tint.  It  is  an  easy  matter 
to  add  more  pigment  to  the  base,  if  it  is  needed,  to  bring 
it  to  the  intended  tint,  but  it  is  impossible  to  take  it  out 
if  the  addition  has  been  overdone.  This  overdosing  is 
called,  in  painter's  parlance,  drowning  the  miller. 

Tints  made  by  the  simple  addition  of  one  coloring  pig- 
ment to  the  base  are  readily  handled  by  following  the  above 
directions. 

MIXING  COMPOUND  TINTS 

If  more  than  one  coloring  pigment  is  required  to  pro- 
duce a  given  tint,  the  first  in  importance  in  the  mixture 
should  be  added  to  the  base  up  to  a  point  just  short  of 
that  which  it  is  thought  its  due  proportion  should  enter 
into  the  compound.  The  next  one  in  importance  should 
then  be  added  to  the  base,  and  that,  too,  stopped  short  of 
that  which  it  is  thought  it  should  be,  and  the  same  process 
continued  for  each  pigment  entering  the  compounding  of 
the  tint.  After  the  mass  has  been  well  stirred,  and  has 
become  uniform  throughout,  it  will  then  be  an  easy  mat- 
ter to  add  a  bit  more  of  this  or  that  color,  if  t'here  is  need 
of  it,  to  bring  it  to  the  exact  shade  of  the  tint  that  is  to 
be  matched. 


240  MODERN  PIGMENTS 

-  If  one  has  been  careful  to  stop  short  of  the  quantity 
thought  to  be  required,  as  is  easily  seen,  it  will  be  readily 
remedied;  but  if,  on  the  contrary,  one  has  not  stopped 
in  time,  and  has  overdone  it,  putting  too  much  of  the 
pigment  in  it,  then  the  mending  will  be  more  difficult. 
It  will  require,  in  the  first  place,  an  increase  in  the  quan- 
tity of  the  base,  proportionate  to  the  excess  of  coloring 
pigment  used  over  and  above  the  right  amount,  so  that 
one  will  be  forced  to  mix  up  a  larger  quantity  of  the  tint 
than  was  intended  or  may  be  required,  which  means  a 
loss. 

If  one  has  poured  in  too  much  through  accident,  and 
is  aware  of  it,  it  is  sometimes  possible  to  dip  out  the  color 
so  poured  in,  or  the  most  of  it,  before  it  has  been  mixed 
with  the  base;  it  will  then  not  be  necessary  to  add 
much,  if  any,  of  the  base  color.  The  waste  is  then 
reduced  to  a  minimum.  Then  proceed  to  thoroughly  mix, 
after  which  add  the  other  coloring  pigments,  as  directed, 
and  lastly  a  portion  of  that  which  was  dipped  out  —  just 
so  much  as  is  needed  to  bring  the  tint  to  the  desired 
shade.  The  remnant  will  be  so  small  a  loss,  that,  in  com- 
parison with  the  other  waste  mentioned,  it  will  be  hardly 
worth  speaking  about. 

PREPARING  TINTS  READY  FOR  USE 

When  a  tint  has  been  compounded  to  the  perfect  satis- 
faction of  the  mixer,  as  when  the  lead  has  been  well 
broken  up  and  used,  as  it  should  have  been,  in  the  form 
of  a  very  stiff  paste,  and  if  the  tinting  pigments  have 
been  thinned  well,  so  they  could  be  easily  incorporated 
with  the  base,  and  the  whole  has  been  well  stirred  up  so 
that  the  paste  is  of  a  uniform  consistency  throughout, 
it  will  be  found  rather  stiff  —  much  too  stiff  for  application 
with  a  brush.  But  the  condition  it  is  in  then  is  just  the 


THE  COMPOUNDING  OF  PIGMENTS  241 

right  one  for  transportation,  as  it  can  be  dipped  out  into 
stock  pails  and  transferred  to  the  job  where  it  is  to  be 
used,  without  any  danger  of  its  slopping  out,  as  it  would 
surely  do  had  it  been  thinned  out  to  the  point  needed 
for  its  application. 

It  is,  of  course,  impossible  to  give  very  definite  direc- 
tions about  the  thinning,  as  circumstances  vary  so  much 
that  the  experience  of  the  man  behind  the  brush  must 
be  used  here.  No  directions,  other  than  the  most  com- 
monplace ones,  can  be  given,  i.e.,  thin  out  more  for  first 
and  second  coats  than  for  third,  and  more  all  around  for 
spongy  surfaces  than  for  such  as  have  little  or  no  pene- 
tration. 

The  above  directions  will  suffice  to  enable  anyone  to 
mix  tints  properly  —  in  oil. 

For  coach  painting,  the  same  care  must  be  exercised 
as  directed  for  tints  made  in  linseed  oil  in  adding  the 
coloring  pigments  to  the  base,  the  main  difference  being 
in  the  thinner,  which  is  either  japan  or  varnish  and 
volatile  oils.  There  is  little,  if  any,  compounding  of  tints 
in  coach  painting,  the  colors  used  for  that  work  being 
self  ones,  or,  if  compounded  at  all,  that  is  usually  done  at 
the  factory. 

For  distemper  painting,  the  pigments  coloring  the 
base  —  which  is  usually  whiting  —  should  be  mixed 
separately  as  for  oil  colors,  only  that  they  should  be 
made  more  fluid ;  otherwise ,  all  that  was  said  before 
applies  to  them  also.  The  thinning  fluid  being  water, 
instead  of  linseed  oil,  japan,  or  varnish.  After  the  tint 
has  been  finished  to  the  satisfaction  of  the  mixer,  the 
melted  glue  or  the  dissolved  gum  arabic  can  be  added. 
It  is  much  more  difficult  to  tint  shades  up  to  a  given 
sample  in  distemper  than  it  is  in  the  preceding  vehicles, 
for  the  reason  that  pigments  mixed  in  water  do  not 


242  MODERN  PIGMENTS 

appear  the  same  as  when  dry,  which  in  oily  mediums 
they  do.  In  water  they  appear  very  much  darker  than 
they  are  after  drying.  There  are  no  exceptions  to  that 
universal  peculiarity,  so  that  a  tint  mixed  to  the  exact 
shade  of  a  dry  sample,  when  first  applied,  would  be  entire- 
ly too  light  when  dry.  The  tints  should  be  made  very  much 
darker  than  the  sample  to  be  matched,  and  a  small  patch 
should  be  painted  over  a  piece  of  paper,  and  the  same 
placed  in  a  warm  sunny  spot  or  over  a  stove  so  the  water 
will  evaporate  quickly,  and,  when  dry,  the  tint  can  then 
be  compared  to  the  sample,  and  if  not  deep  enough  more 
of  the  tinting  pigment  must  be  added  until  the  tint  has 
attained  the  same  tone  as  that  of  the  sample.  This  may 
require  several  times  testing  it,  by  drying  it  upon  the 
piece  of  paper,  but  it  is  the  only  safe  way,  and  any 
other  method  would  be  but  guess  work. 

It  requires  considerably  more  experience  on  the  part 
of  the  mixer  to  hit  a  tint  just  right  in  a  quick  way.  Few 
men  can  fall  into  it  at  once.  In  time,  the  experience 
gained  by  many  former  failures  will  gradually  work  up 
into  intuition,  for  that  is  what  it  seems  to  the  man  who 
has  tried  it  a  few  times  but  could  not  do  it. 


CHAPTER  XXV 

A  LIST  OF  SOME  OF  THE  PRINCIPAL  TINTS  AND  How  TO 
MAKE  THEM 

General  Remarks 

IT  is  deplorable  that  the  English  language  has  no 
well-defined  nomenclature  to  designate  tints.  As  other 
languages  have  not  got  any  either,  it  is  not  behind  them 
any  in  this  regard;  but  it  is  deplorable  nevertheless. 

If  one  is  inclined  to  doubt  this,  let  him  procure  the 
color  cards  of  a  dozen  manufacturers  of  mixed  paints, 
where  the  tints  are  known  and  sold  by  name,  as  well  as 
by  number,  and  these  names  printed  under  the  tints. 
It  will  be  found  upon  inspection  that  it  will  be  rare  if  any 
two  out  of  the  dozen  look  alike.  This  is  especially  true 
of  the  neutral  tints,  or  those  tints  which  are  neither 
primary,  secondary,  nor  tertiary.  Owing  to  this  lack  of 
uniformity,  some  persons  may  think  that  they  have  not 
been  successful  in  obtaining  the  right  tint  if  they  get 
something  which  does  not  come  up  to  their  conception 
of  what  the  tint  ought  to  be,  and  may  think  that  the 
directions  given  as  to  how  to  make  them  are  wrong, 
or  that  the  colors  used  in  the  making  were  off;  all  but 
the  right  conclusion  perhaps  —  that  what  they  call  a 
gray  may  be  somebody  else's  drab.  If  he  follows  the 
directions  for  making  a  gray,  and  his  own  ideas  of  a 
drab  being  that  the  gray  fits  them,  it  will  certainly  be 
a  hard  matter  to  convince  him  that  he  is  wrong,  because 
there  is  no  accepted  standard  recognized  to  settle  it 

243 


244  MODERN  PIGMENTS 

beyond  dispute.  Again,  if  the  directions  be  given  for  the 
making  of  a  sage  green,  and  the  tint  happens  to  be  what 
he  conceives  is  a  myrtle  green,  or  an  apple  green  or  a  light 
olive,  who  will  say  that  he  is  wrong?  Surely,  when 
well-trained  men  differ  so  widely  among  themselves,  how 
can  others,  who  have  only  given  the  study  of  color  the 
most  superficial  examination,  be  expected  to  do  better  ? 
Nature  itself  varies  exceedingly,  and  tints  which  are 
named  after  the  prevailing  tones  of  green  of  certain 
trees  or  plants  are  bound  to  form  a  subject  of  endless 
and  profitless  controversies  as  to  what  is  the  proper  tint. 
Take  instances,  outside  of  the  vegetable  kingdom,  out 
of  that  of  animals :  Peacock  blue  —  where  is  the  standard 
for  that?  Let  anyone  undertake  to  furnish  one,  and  out 
of  a  dozen  men,  at  least  ten  would  demur  to  it!  If  the 
whole  dozen  undertook  to  furnish  the  standard,  there 
would  be  precisely  twelve  supplied. 

So,  when  directions  are  given  for  the  making  of  such 
far-fetched  named  tints  that  fashion  has  given  birth  to, 
such  as  baby  elephant's  breath,  cataract's  mist,  etc., 
would  many  be  found  sufficiently  aesthetic  to  forthwith 
fall  into  the  idea  of  it,  or,  if  they  did,  would  they  coincide 
as  to  the  proper  tints  to  represent  them? 

These  precautionary  words  are  necessary  to  warn  the 
reader  that  he  must  not  expect  too  much  (or  the  impossi- 
ble) from  the  general  directions  given  for  the  compound- 
ing of  tints  by  name.  The  quantity,  by  weight,  of  pig- 
.  ment  to  be  used  in  producing  them  has  been  left  blank 
for  the  very  purpose  of  enabling  the  mixer  to  suit  himself 
if  possible  as  to  the  depth,  and  in  more  than  two  pig- 
ment compounds  to  some  extent  as  to  the  tone.  This 
will  give  the  mixer  a  chance  to  use  some  judgment  of 
his  own,  and  if  he  has  noted  the  direction  given,  not  to 
drown  the  miller.  He  will  have  the  tint  light  enough  so 


THE  PRINCIPAL  TINTS  245 

that  he  can  add  more  of  the  coloring  pigments  named 
to  produce  the  tint  of  such  depth  and  tone  as  he  requires 
it  to  be. 

There  is  still  another  very  important  reason  why 
weights  are  not  given.  It  must  have  been  made  very 
plain  to  the  readers  of  this  treatise,  who  have  followed 
the  descriptions  given  with  each  pigment,  that  there  is 
a  vast  difference  in  the  strength  of  coloring  matter  con- 
tained in  a  given  weight  of  various  samples  of  most  of 
them.  If  one  man  took  a  recipe  made  up  in  pounds  and 
ounces  he  would  obtain  a  tint  that  would  bear  no  resem- 
blance to  that  obtained  by  the  very  same  recipe  in  some 
other  locality,  where  the  coloring  pigments  were  made  up 
by  another  manufacturer.  Thus,  if  a  recipe  should  say: 

Take  White  lead  .    .    .    .    .    .    .    .  20  pounds 

Venetian  red 3 

Medium  chrome  yellow     .    .      1          " 

If  operator  No.  1,  should  use  a  pure  chrome  yellow  and 
a  good-toned  Venetian  red;  operator  No.  2,  of  the  same 
town,  using  a  chrome  yellow,  containing  but  20  per  cent 
of  color,  and  an  indifferent  Venetian  red,  would  have  an 
entirely  different  tint,  and  it  would  be  due  to  the  recipe 
giving  precise  weights.  Had  the  same  been  left  blank, 
the  chances  are  that  the  difference  would  not  have  been 
so  great  —  at  any  rate,  the  mixer  would  have  had  some- 
thing nearer  to  his  liking. 

LIST  OF  PRINCIPAL  TINTS 

For  the  purpose  of  easy  reference  in  the  finding  of  any 
particular  tint,  they  have  been  listed  alphabetically. 

The  base  pigment,  or  the  principal  one  of  the  com- 
pound, is  invariably  named  first.  The  other  coloring 
pigments  are  named  in  the  order  of  their  importance 


246  MODERN  PIGMENTS 

in  the  make  up  of  the  tints.  Therefore,  of  the  last, 
frequently  but  a  very  small  portion  need  be  added. 
As  far  as  possible,  where  a  simple  tinge  or  reflection  of  a 
color  is  needed  this  will  be  indicated : 

Acacia.  Lamp  black  for  base ;  color  it  up  with  Indian  red  and 
tinge  with  Prussian  blue. 

v  Acorn  Brown.  Similar  to  chocolate  which  see  —  but  lightened 
with  white  lead. 

Alderney  Brown.  Lamp  black;  orange  chrome  yellow;  Fr. 
ocher;  white  lead. 

Amber  Brown.  Burnt  sienna  for  base;  add  orange  chrome 
yellow,  burnt  umber,  a  trifle  of  lamp  black,  lighten  shade  to 
suit  by  adding  white  lead. 

Amaranth.  Tuscan  red  and  vermilion  in  about  equal  parts 
for  base;  add  enough  ultramarine  blue  to  suit  shade  of  it  wanted. 

Anemone.  Vermilion  red  for  base;  Prussian  blue  and  a  little 
black  and  white  lead. 

Alabaster.  White  lead  for  base.  Give  it  a  very  faint  tinge 
of  medium  chrome  yellow. 

Apple  Green.  White  lead  for  base;  add  light  chrome  green 
and  orange  chrome  yellow. 

Antique  Bronze.  Orange  chrome  yellow  for  base;  add  ivory 
black ;  lamp  black  can  be  substituted,  but  the  shade  will  not  be 
so  rich. 

v;  Apricot.   Medium  chrome  yellow  for  base;  Venetian  red,  car- 
mine lake,  if  light  shade  is  wanted  lighten  it  up  with  white  lead. 

Armenian  Red.  Bright  Venetian  red  for  base ;  lighten  up  with 
French  ocher. 

Ash  Gray.  White  lead  for  base;  tinge  with  lamp  black,  add 
a  bit  of  French  ocher. 

Asiatic  Bronze.  Raw  umber  for  base ;  medium  chrome  yellow 
to  which  add  sufficient  white  lead  to  suit  shade  wanted. 

Ashes  of  Roses.  Light  Tuscan  red  for  base,  to  which  add  a 
trifle  of  lamp  black. 

Autumn  Leaf.  White  lead  for  base,  to  which  add  French 
ocher,  orange  chrome  yellow,  a  trifle  of  Venetian  red,  sufficient 
to  slightly  redden  tone  with  more  of  it,  if  a  deeper-toned  red 
is  desired. 


THE  PRINCIPAL  TINTS  247 

Azure  Blue.  White  lead  for  base ;  add  Prussian  blue  to  shade 
desired  of  it. 

Bay.  Lamp  black  for  base;  add  Venetian  red  and  orange 
chrome  yellow. 

Begonia.  Lamp  black ;  vermilion  red  of  a  good  scarlet  shade, 
tinge  with  Prussian  blue. 

Bismark  Brown.  Burnt  sienna  for  base;  add  burnt  umber, 
orange  chrome  yellow.  Lighten  slightly  with  white  lead  to 
suit. 

Black  Slate.  Lamp  black  for  base;  Prussian  blue,  slightly 
lightened  up  with  white  lead.  % 

Bordeaux  Blue.  Lamp  black  for  base;  orange  chrome  yellow, 
Prussian  blue. 

Bottle  Green.  Prussian  blue  and  lamp  black  for  base,  and 
lemon  chrome  yellow.  To  obtain  this  tint  at  its  best,  it  should 
be  glazed  over  afterwards  with  a  yellow  lake. 

Brass.  White  lead  for  base;  add  medium  chrome  yellow; 
French  ocher  to  tint  wanted. 

Bronze  Red.  Vermilion  red  for  base;  orange  chrome  yellow; 
lamp  black. 

Brown  Stone.  Tuscan  red  for  base;  add  orange  chrome  yel- 
low; lamp  black;  lighten  up  to  suit  with  white  lead. 

Brick  Color.  Yellow  ocher  for  base;  add  Venetian  red  to 
suit,  for  very  light  shades  add  white  lead  in  very  small  quantity. 

Bronze  Green.  Extra  dark  chrome  green  for  base;  add  lamp 
black.  This  makes  a  fair  bronze  green.  If  extra  dark  chrome 
green  is  not  obtainable,  use  the  dark  or  even  medium  chrome 
green  with  more  of  the  lamp  black  to  darken  the  tint. 

Another  recipe  is  given  for  a  richer  tone  of  it ;  medium.chrome 
green  for  base;  add  ivory  black  and  a  trifle  of  raw  umber  to 
shade  wanted. 

Bronze  Yellow.  Medium  chrome  yellow  for  base;  raw  umber; 
lighten  up  with  white  lead. 

Browns,  all  shades  and  Brown  Drabs.  Venetian  red  for  base; 
add  French  ocher  and  lamp  black  in  various  proportions  accord- 
ing to  the  shade  of  brown  wanted.  For  the  brown  drabs  add 
white  lead  to  the  above  brown  tints,  to  the  desired  shade. 

Buttercup.  White  lead  for  base ;  add  lemon  chrome  yellow 
to  suit. 


248  MODERN  PIGMENTS 

Cambridge  Red.   Vermilion  for  base ;  add  Prussian  blue  to  suit. 

Cafe  au  lait.  Burnt  umber  for  base;  add  white  lead;  French 
ocher;  Venetian  red. 

Carnation.  English  vermilion  for  base;  add  some  good 
madder  lake  or  carmine.  If  desired  very  light,  add  some  zinc 
white. 

Cerulean  Blue.  Zinc  white  for  base;  add  ultramarine  blue, 
but  better  use  cobalt  if  procurable  and  genuine. 

Cherry  Red.  Vermilion  for  base;  add  burnt  sienna; 
crimson  lake;  ultramarine  blue. 

Chamois.  White  lead  for  base ;  add  French  ocher ;  medium 
chrome  yellow  to  suit. 

Chatnoline.  White  lead  for  base;  add  raw  sienna;  lemon 
chrome  yellow  to  suit. 

Chartreuse.  White  lead  for  base;  add  medium  chrome 
yellow;  medium  chrome  green. 

Chestnut.  Venetian  red  for  base;  add  medium  chrome 
yellow;  French  ocher  and  lamp  black. 

t/  Chocolate.  Burnt  amber  for  base;  add  some  rich  crimson 
vermilion  or  madder  lake. 

Another  way  is  French  ocher  for  base;  add  lamp  black  and 
a  little  Venetian  red  to  suit. 

Canary.     Use  the  chrome  yellow  sold  under  that  name. 
Another  way  is  to  take  lemon  chrome  yellow  to  which  add 
zinc  white  to  reduce  to  tint  wanted. 

Claybank.  French  ocher  for  base;  add  orange  chrome 
yellow;  lighten  up  to  shade  wanted  with  white  lead. 

Claret.  Madder  lake  and  ultramarine  blue  for  base,  to  which 
add  some  English  vermilion  and  ivory  black. 

Clay  Drab.  White  lead  for  base;  medium  chrome  yellow; 
raw  and  burnt  sienna. 

Cinnamon.  White  lead  for  base;  add  burnt  sienna;  French 
ocher;  medium  chrome  yellow. 

\J  Cobalt  Blue.  This  is  a  solid  blue.  Use  blue  sold  under  that 
name.  If  not  obtainable,  take  good  ultramarine  blue  for  base, 
to  which  add  sufficient  zinc  white  to  lighten  it  to  shade  required. 

Coral  Pink.  Vermilion  for  base ;  white  lead ;  medium  chrome 
yellow. 


THE  PRINCIPAL  TINTS  249 

Colonial  Yellow.  White  lead  for  base;  add  medium  chrome 
yellow;  orange  chrome  yellow  to  tinge  it 

Cocoanut  Brown.  Burnt  umber  for  base;  lighten  up  with 
white  lead. 

Cotrine.  White  lead  for  base;  add  orange  chrome  yellow  and 
lamp  black. 

Cream  Color,  and  all  the  buffs.  White  lead  for  base;  add  some 
good  French  or  Oxford  ocher  to  tint  wanted ;  this  will  make  all 
the  cream  and  buff  tints  from  very  light  to  very  dark  by  adding 
more  or  less  of  the  ocher. 

Copper.  Medium  chrome  yellow  for  base;  add  Venetian  red 
and  a  little  of  lamp  black. 

Citron.  Venetian  red  for  base;  add  medium  chrome  yellow 
with  some  Prussian  blue  just  to  tinge.  If  too  dark,  lighten  up 
with  white  lead. 

Crimson.  Dark  English  vermilion  or  any  of  the  dark  shades 
of  vermilion  reds.  If  desired  very  rich  toned,  add  some  good 
madder  lake  or  carmine. 

Dove  Color.  White  lead  for  base;  add  ultramarine  blue; 
Indian  red  and  lamp  black. 

Dregs  of  Wine.  Dark  Tuscan  red  for  base;  lamp  black  and 
a  trifle  of  zinc  white. 

Electric  Blue.  Ultramarine  blue  for  base;  add  white  lead 
and  raw  sienna. 

Ecru.  White  lead  for  base ;  add  French  ocher ;  burnt  sienna ; 
lamp  black.  This  tint  varies  greatly.  Its  meaning  is  raw 
and  is  intended  to  represent  the  color  of  raw  flax,  before  it  is 
bleached. 

Emerald.  Paris  green  as  it  is  or  an  imitation  of  it  made  from 
a  very  pale  chrome  green  of  a  bluish  cast  or  slightly  tinged  with 
Prussian  blue. 

Egyptian  Green.  White  lead  for  base;  add  raw  umber;  lemon 
chrome  yellow;  Prussian  blue  to  suit. 

Fawn.  White  lead  for  base;  add  medium  chrome  yellow; 
Venetian  red;  burnt  umber. 

Flesh  Color.  White  lead  for  base;  add  medium  chrome  yel- 
low; French  ocher;  and  Venetian  red. 


250  MODERN   PIGMENTS 

French  Gray.  White  lead  for  base;  add  ivory  black  with  a 
faint  tinge  of  ultramarine  blue  and  madder  lake  or  carmine. 

French  Red.  Indian  red  for  base;  add  English  vermilion  to 
brighten  it,  then  glaze  with  madder  lake  or  carmine. 

Gazelle.  French  ocher  for  base ;  add  dark  Tuscan  red ;  Vene- 
tian red;  lamp  black;  lighten  up  with  white  lead. 

Geranium.  Vermilion  red  for  base;  add  Indian  red  and 
lamp  black. 

Gobelin  Blue.  Ivory  black  for  base ;  a.dd  white  lead ;  Prussian 
blue;  medium  chrome  green. 

Gold.  White  lead  for  base ;  add  medium  chrome  yellow ;  some 
good  French  ocher;  and  a  very  little  vermilion  red  or  English. 

Golden  Brown.  French  ocher  for  base;  add  orange  chrome 
yellow;  lamp  black;  lighten  up  with  white  lead  to  suit. 

Gray  Green.  White  lead  for  base;  add  ultramarine  blue; 
lemon  chrome  yellow;  lamp  black. 

Grass  Green.  Extra  light  chrome  green  just  as  it  comes  from 
the  can.  For  an  extra  fine  job  glaze  with  Paris  green. 

Green  Stone.  White  lead  for  base ;  add  medium  chrome  green ; 
raw  umber,  and  French  ocher. 

Gray  Stone.  White  lead  for  base;  add  lamp  black;  Prussian 
blue;  Venetian  red. 

Gray  Drabs.  All  shades  of  them.  White  lead  for  base ;  add 
lamp  black  or  ivory  black  with  a  little  burnt  umber  in  various 
proportion  according  as  a  light  or  deep  shade  of  drab  is  desired. 

Greys.  Light '  to  dark  shades.  White  lead  for  base ;  lamp 
black  in  various  proportions  to  suit  shade  wanted. 

Hay  Color.  White  lead  for  base;  add  orange  chrome  yellow; 
light  chrome  green;  Indian  red. 

Heliotrope.  Zinc  white  for  base;  add  bright  Venetian  red; 
ultramarine  blue. 

Indian  Pink.   White  lead  for  base ;  add  Indian  red. 

Indian  Brown.  Indian  red  for  base;  add  lamp  black;  French 
ocher. 

Iron  Gray.  Lamp  black  for  base;  add  white  lead  and  a  trifle 
of  orange  chrome  yellow. 


THE   PRINCIPAL  TINTS  251 

Ivy  Green.  French  ocher  for  base;  add  lamp  black;  Prussian 
blue. 

Jasper.  Lamp  black  for  base ;  add  white  lead ;  medium  chrome 
yellow;  light  Indian  red. 

Jonquil.  White  lead  for  base;  add  medium  chrome  yellow 
to  which  should  be  added  a  tinge  of  red  with  English  pale  ver- 
milion to  enrich  it. 

Lavender.  White  lead  for  base ;  add  ivory  black ;  ultramarine 
blue;  tinge  with  carmine  or  madder  lake. 

Lead  Color.  White  lead  for  base ;  add  lamp  black  and  a  trifle 
of  Prussian  blue.  The  latter  can  be  omitted,  if  the  lamp  black 
is  good. 

Leather.  French  ocher  for  a  base;  add  burnt  umber.  If  a 
warm  tone  of  it  is  desired,  add  some  Venetian  red. 

Lemon.   Use  lemon  chrome  yellow  just  as  it  is. 

Leaf  Buds.  White  lead  for  base;  add  orange  chrome  yellow; 
light  chrome  green. 

Lilac.    White  lead  for  base;  add  dark  Indian  red  to  suit. 

London  Smoke.  Yellow  ocher  for  base ;  add  ultramarine  blue ; 
lamp  black;  lighten  up  to  suit  with  white  lead. 

Magenta.  Vermilion  for  a  base;  add  carmine  or  madder  lake 
with  a  tinge  of  ultramarine  blue. 

Mauve.  Yellow  ocher  for  base;  add  Venetian  red;  lamp 
black;  lighten  up  to  suit  with  white  lead. 

Mastic.  White  lead  base;  add  French  ocher;  Venetian  red, 
a  trifle  of  lamp  black. 

Maroon.  Carmine  or  madder  lake  for  base;  add  ivory  black 
and  a  small  part  of '  orange  chrome  yellow  —  another  way ; 
Tuscan  red  for  base;  add  orange  chrome  yellow  with  a  trifle  of 
ivory  black. 

Manila  or  Deck  Paint.  White  lead  for  base;  French  ocher; 
medium  chrome  yellow. 

Marigold.  Medium  chrome  yellow  for  base;  add  white  lead; 
orange  chrome  yellow. 

Mexican  Red.   Bright  Venetian  red  for  base;  red  lead. 

Mignonette.  Medium  chrome  green  for  base;  add  Prussian 
blue;  medium  chrome  yellow;  lamp  black. 


252  MODERN   PIGMENTS 

Moorish  Red.  Vermilion  red  for  base;  add  rose  pink  or, 
what  is  much  better,  madder  lake. 

Mouse  Color.  White  lead  for  base;  add  lamp  black,  a  tinge 
of  Venetian  red  and  burnt  umber. 

Moss  Rose.  Lemon  chrome  yellow  for  base;  add  medium 
chrome  green;  lighten  with  white  lead  to  suit. 

Mulberry.  Ivory  black  for  base;  add  vermilion  red;  trifle 
Prussian  blue. 

Myrtle  Green.  Dark  chrome  green  for  base;  add  ultramarine 
blue;  lighten  up  with  white  lead  to  suit. 

Nile  Blue.  White  lead  for  base;  add  Prussian  blue;  with  a 
trifle  of  medium  chrome  green. 

Normandy  Blue.  Medium  chrome  green;  ultramarine  blue;  a 
trifle  of  white  lead. 

Nut  Brown.  Lamp  black  for  base ;  add  Venetian  red ;  medium 
chrome  yellow;  French  ocher. 

Oak  Color.  Light  and  dark  shades  of  it.  White  lead  for 
base ;  add  French  ocher ;  also  a  small  quantity  of  Venetian  red. 
Vary  the  quantities  to  suit  for  light  or  dark  shades. 

Old  Gold.  White  lead  for  base;  add  medium  chrome  yellow; 
French  ocher  and  a  small  portion  of  burnt  umber. 

Olive.  Lemon  chrome  yellow  for  base ;  add  about  equal  parts 
of  Prussian  blue  and  lamp  black.  Some  shades  of  olive  can  be 
made  by  substituting  French  ocher  for  the  lemon  yellow;  in 
such  a  case  the  tone  will  not  be  so  bright.  A  trifle  of  the  lemon 
chrome  yellow  added  to  the  ocher  will  improve  it  and  make 
still  another  variety  of  olive  tones. 

Orange.  Orange  chrome  yellow,  just  as  it  comes  from  the 
can.  If  not  to  be  had,  take  medium  chrome  yellow  and  color 
it  up  with  a  bright  scarlet  red  —  any  scarlet-toned  vermilion 
will  do. 

Olive  Brown.  Raw  umber  for  base ;  add  lemon  chrome  yellow. 
Vary  the  quantity  to  suit  the  intensity  of  shade  wanted. 

Orange  Brown.  Orange  chrome  yellow  for  base;  add  raw 
sienna;  a  trifle  of  burnt  umber. 

Oriental  Green.  Raw  umber  for  base;  add  lemon  chrome 
yellow  to  suit. 


THE   PRINCIPAL  TINTS  253 

Opal  Gray.  White  lead  for  base;  add  burnt  sienna;  ultra- 
marine blue. 

Peach  Blossom.  White  lead  for  base;  add  pale  Indian  red  to 
suit.  A  tinge  of  madder  lake  will  enrich  it,  but  is  not  a 
necessity. 

Pearl.  White  lead  for  base;  add  ivory  black  and  a  trifle  of 
ultramarine  blue  and  carmine  red.  It  is  a  very  light  shade, 
just  off  the  white;  do  not  overdo  it. 

Pea  Green.   White  lead  for  base;  add  medium  chrome  green 

to  suit. 

Peacock  Blue.  Ultramarine  blue  for  base;  add  extra  light 
chrome  green  and  zinc  white  to  suit. 

Persian  Orange.  Orange  chrome  yellow  for  base;  add  French 
ocher;  white  lead. 

Pink.  Zinc  white  for  base;  add  madder  lake  or  carmine  or 
the  crimson  shades  of  English  vermilion. 

Pompeian  Red.  Vermilion  red  base;  add  orange  chrome 
yellow;  ivory  black. 

Pompeian  Blue.  White  lead  base;  add  ultramarine  blue; 
vermilion  red;  French  ocher. 

Plum  Color.  White  lead  for  base;  add  Indian  red;  ultra- 
marine blue. 

Portland  Stone.  French  ocher  for  base;  add  raw  umber; 
lighten  up  with  white  lead. 

Pistache.  Ivory  black  for  base;  add  French  ocher;  medium 
chrome  green. 

Purple.  White  lead  for  base;  add  dark  Indian  red;  a  trifle  of 
light  Indian  red  to  suit. 

Primrose.  White  lead  for  base ;  add  lemon  or  medium  chrome 
yellow,  according  to  the  shade  wanted  of  it. 

Purple  Brown.  Dark  Indian  red  for  base;  add  ultramarine 
blue ;  a  trifle  of  lamp  black  and  white  lead  to  lighten  it  up. 

Quaker  Green.  White  lead  for  base;  add  French  ocher;  lamp 
black  and  burnt  sienna. 

Roan.  Lamp  black  for  base;  add  Venetian  red;  Prussian 
blue ;  lighten  it  up  to  suit  with  white  lead. 


254  MODERN   PIGMENTS 

Robin's  Egg  Blue.  White  lead  for  base;  add  ultramarine 
blue  until  the  shade  is  a  pretty  deep  blue,  then  add  some  pale 
or  medium  chrome  green  to  suit  tone  desired  of  it. 

Russet.  White  lead  for  base;  add  orange  chrome  yellow;  a 
trifle  of  lamp  black. 

Russian  Gray.  White  lead  for  base;  add  ultramarine  blue; 
pale  Indian  red  and  lamp  black. 

Sage  Green.  White  lead  for  base;  add  medium  chrome  green 
until  the  tint  is  nearly  but  not  quite  a  pea  green,  then  add  lamp 
black  to  bring  it  to  the  sage  color. 

Salmon.  White  lead  for  base ;  add  French  ocher ;  burnt  sienna ; 
with  a  trifle  of  English  vermilion  or  a  good  vermilion  red. 

Sapphire  Blue.    Zinc  white  for  base;  add  ultramarine  blue. 

Sap  Green.  White  lead  base;  add  medium  chrome  yellow; 
lamp  black. 

Sea  Green.   White  lead  base;  add  Prussian  blue;  raw  sienna. 

Seal  Brown.  Burnt  umber  for  base;  add  good  French  ocher 
and  a  trifle  of  white  lead. 

Scarlet.  Pale  English  vermilion  or  any  of  the  scarlet-toned 
vermilion  reds. 

Shrimp  Pink.  White  lead  for  base ;  add  Venetian  red ;  burnt 
sienna  and  a  trifle  of  vermilion. 

Sky  Blue.  White  lead  for  base;  add  Prussian  blue  to  shade 
wanted. 

Slate.  White  lead  for  base ;  add  raw  umber ;  ultramarine  blue ; 
lamp  black. 

Spruce  Yellow.  French  ocher  for  base;  add  Venetian  red; 
lighten  up  with  white  lead  to  suit. 

Snuff  Color.  French  ocher  for  base;  add  burnt  umber  and  a 
bit  of  Venetian  red. 

Straw  Color.  Medium  chrome  yellow  for  base;  add  French 
ocher;  a  bit  of  Venetian  red;  lighten  up  with  white  lead. 

Stone  Color  and  Yellow  Drabs.  White  lead  for  base;  add 
French  ocher;  tinge  up  with  medium  chrome  yellow  and  burnt 
umber.  By  varying  quantities  all  shades  of  yellow  drabs  can 
be  made. 

Tan.  White  lead  for  base;  add  burnt  sienna  and  a  trifle  of 
lamp  black. 


THE   PRINCIPAL  TINTS  255 

Tally-Ho.  White  lead  for  base ;  add  French  ocher ;  Venetian 
red ;  dark  chrome  green  with  a  bit  of  ivory  black. 

Terra  Cotta.  French  ocher  for  base;  add  Venetian  red  and 
white  lead.  Some  shades  of  it  require  the  addition  of  Indian 
red.  Some  rich  shades  are  sometimes  desired  under  that  name ; 
use  orange  chrome  yellow  in  place  of  French  ocher,  add  Vene- 
tian red  and  a  trifle  of  burnt  umber  to  suit. 

Turquoise  Blue.  White  lead  for  base,  or  better,  zinc  white; 
add  cobalt  blue ;  Paris  green  or  pale  chrome  green. 

Vienna  Brown.  Burnt  umber  for  base;  add  Venetian  red; 
French  ocher;  and  lighten  with  white  lead  to  suit. 

Violet.  White  lead  for  base;  add  pale  Indian  red,  and  a 
trifle  of  dark  Indian  red. 

Willow  Green.  White  lead  for  base;  add  sufficient  medium 
chrome  yellow  to  make  a  pretty  deep  shade;  then  add  a  small 
quantity  of  raw  umber  and  ivory  black. 

Wine  Color.  English  vermilion  or  scarlet-toned  vermilion 
red  for  base;  add  madder  lake  or  carmine;  ultramarine  blue; 
ivory  black. 

Another  way;  dark  Tuscan  red  of  good  quality  to  which  add 
a  trifle  of  ivory  black. 

Water  Green.  White  lead  for  base;  add  raw  sienna;  dark 
chrome  green. 

Yellow  Bronze.  Lemon  or  medium  chrome  yellow  for  base; 
add  French  ocher  and  just  a  trifle  of  burnt  umber. 


INDEX 


A. 

Acacia,  246. 
Acorn  brown,  246. 
Adulterants   of  white  lead,  25. 
Adulteration  of  chrome  yellow, 
Alabaster,  246. 
Alderney  brown,  246. 
Alizarin,  120. 
Aluminous  ocher,  58. 
Amaranth,  246. 
Amber  brown,  246. 
American  ochers,  70,  183. 
American  sienna,  187. 
American  umber,  187. 
American  vermilion,  104,  184. 
American  zinc,  25. 
Analysis  of  Oxford  ocher,  65. 
Analysis  of  terre  verte,  140. 
Analysis  of  umber,  162. 
Anemone,  246. 
Antique  bronze,  246. 
Antwerp  blue,  187. 
Apple  green,  246. 
Apricot,  246. 
Armenian  red,  246. 
Artificial  ocher,  183. 
Ash  gray,  246. 
Ashes  of  roses,  246. 
Asiatic  bronze,  246. 
Aureolin,  87,  183. 

properties  of,  87. 
Aurora  yellow,  184. 
Autumn  leaves,  246. 


Azure  blue,  247. 
Azurite,  187. 

B. 

Barium  chromate,  183. 
Baryta  lemon  yellow,  78,  183. 

properties  of,  78. 
Baryta  white,  51,  183. 

composition  of,  51. 

properties  of,  52. 

source  of  supply  of,  51. 

uses  as  an  adulterant,  53. 
Baryta    white    artificially    made, 
54. 

as  a  distemper  color,  55. 
Baryta  yellow,  183. 
Barytes,  183. 

Base  (the)  in  mixing  tints,  237. 
Basic  copper  acetate,  145,  186. 
Bay,  247. 
Beeswax,  217. 
Begonia,  247. 
Benzine,  208. 

properties  of,  208. 

uses  of,  209. 
Berg  blau,  187.  ' 
Berg  grim,  186. 
Berlin  blue,  187. 
Best  vehicle  for  white  lead,  22. 
Bice,  187. 

Bismark  brown,  247. 
Black  lead  (see  graphite),  188. 
Black  pigments,  170. 
Black  pigments,  188. 


257 


258 


INDEX 


Black  slate,  247. 
Blanc  d 'argent,  182. 
Blanc  de  plomb,  182. 
Blanc  de  zinc,   182. 
Blanc  fixe,  183. 
Bleu  d'azur,  186 
Bleu  de  Berlin,  187. 
Bleu  de  cobalt,  187. 
Bleu  de  smalte,  187. 
Bleu  de  Thenard,  187. 
Bleu  d'outremer,  186. 
Blow    pipe    test    for    white    lead, 
29. 

how  to  make,  30. 
Blue    black  (see    charcoal    black), 

188. 

Blue  pigments,  186. 
Blue  smalt,  155. 

properties,  155. 
Blue  verditer,  154,  187. 

production  of,  154. 

properties  of,  154. 
Boiled  linseed  oil,  203,  231. 

adulterations  of,  231. 

properties  of,  231. 

uses  of,  231. 
Bordeaux  blue,  247. 
Bottle  green,  247. 
Brass,  247. 
Brick  color,  247. 
Bronze  green,  247. 
Bronze  red,  247. 
Bronze  yellow,  247. 
Brown  ocher,  183. 
Brown  pigments,  187. 
Brown  pink,  184. 
Brown  stone,  247. 
Browns,  247. 
Brun  de  Vandyke,  188. 
Burnt  ocher,  184. 
Burnt,  sieriha,  187. 
Burnt  umber,  159,  187. 

properties  of,  159. 

uses  of,  159. 
Buttercup,  247. 


Cadmium,  92. 

chemistry  of,  92. 

properties  of,  92. 
Cadmium  gelb,  184. 
Cadmium  yellow,  184. 
Cafe  au  lait,  248. 
Cambridge  red,  248. 
Canary,  248. 

Caput  motuum  vitrioli,  184. 
Carbonate    of    lime   (see  whiting), 

41,  182. 

Carbon  black  (see  gas  black),  188. 
Carmin,  184. 
Carmin  de  garance,  185. 
Carmin  lack,  185. 
Carmine,  127,  185. 

history  of,  127. 

properties  of,  127. 

uses  of,  127. 
Carnation,  248. 
Cassel  earth,  188. 
Cendres  blues,  187. 
Cerulean  blue,  187,  248. 
Ceruleum,  153,  187. 

properties  of,  153. 

uses  of,  153. 
Ceruse,  153. 

Chalking  of  white  lead,  21. 
Chamois,  248. 
Chamoline,  248. 
Charcoal  black,  187,  188. 

preparation  of,  178. 

properties  of,  178. 

uses  of,  178. 
Chartreuse,  248. 
Cherry  red,  248. 
Chessylite,  154,  187. 
Chestnut,  248. 

China  clay  (see  kaolin),  183. 
Chinese  blue,  150,  186. 

properties  of,  150. 

uses  of,  150. 
Chinese  vermilion,  184. 
Chinese  white,  182. 


INDEX 


259 


Chocolate,  248. 

Chromate  of  lead,  183,  184. 

Chrome,  183. 

Chrome  green,  129,  185. 

chemistry  of,  129. 

manufacture  of,  130. 

properties  of,  132. 

proprietary  names  for,  131. 

uses  of,  133. 
Chrome  jaune,  183. 
Chrome  yellows,  73,  183. 

chemistry  of,  74. 

general  remarks  on,  73. 

manufacture  of,  74. 

medium,  74. 

properties  of,  74. 

canary  and  lemon,  75,  183. 
manufacture  of,  75. 

orange,  75,  183. 
defects  of,  77. 
manufacture  of,  75,  183. 
properties  of,  76. 
uses  of,  77. 
Chrom  gelb,  183. 
Chromium  sesquioxide,  186. 
Cinnabar,  184. 
Cinnamon,  248. 
Citrine  lake,  184. 
Citron,  249. 
Claret,  248. 
Clay  bank,  248. 
Clay  drab,  248. 
Cobalt  blue,  248. 
Cobalt  blue,  152,  187. 

manufacture  of,  152. 

properties  of,  152. 

uses  of,  152. 
Cobalt  green,  135,  185. 

properties  of,  135. 

uses  of,  135. 

Cobalt  yellow,  (see  aureolin),  183. 
Cocoanut  brown,  249. 
Coelin,  187. 
Coelin  blue,  187. 
Colcothar,  184. 


Collen  earth,  188. 

Cologne  earth,  188. 

Colonial  yellow,  249. 

Coloring  pigments  for  tints,  235. 

Compounding  of  pigments,  187. 

Copper,  249. 

Coral  pink,  248. 

Cotrine,  249. 

Cream  color,  249. 

Cremser  weiss,  182. 

Crimson,  249. 

Crocus,  184. 

Cupric  arsenite,  186. 

Cyprus  umber,  187. 

D. 

Dahl  process  white  lead,  27. 

manufacture  of,  28. 

properties  of,  28. 
Dark  chrome  green,  185. 
Dextrin,  226. 

properties  of,  226. 
Dove  color,  249. 
Dregs  of  wine,  249. 
Drop    black     (see     ivory    black), 

175,  188. 
Dryers,  229. 

general  remarks  on,  229. 

lead  oxides  as  driers,  232. 

oxides  of  manganese,  232. 

paste  form,  233. 
Dumont's  blue,  187. 
Dunkel  gelb  lack,  184. 
Dutch  pink,  90,  184. 

character  of,  90. 

properties  of,  91. 
Dutch  process  white  lead,  9. 

chemistry  of,  11. 

corroding  of,  10. 

E. 

Earth  whites,  40. 
general  remarks,  40. 


260 


INDEX 


Ecru,  249. 

Egyptian  green,  249. 

Electric  blue,  249. 

Elfenbein  schwartz,  188. 

Emerald,  249. 

Emerald  green   (see  Paris  green), 

143. 
Emerald      oxide     of      chromium, 

186. 

English  ochers,  69. 
English  umber,  187. 
English  vermilion  (see  vermilion), 

184. 
Extra  light  chrome  green,  185. 

F. 

Fawn,  249. 
Fixed  oils,  189. 
Flake  white,  22,  182. 
Flaxseed  oil  (see  linseed  oil),  189. 
Flesh  color,  249. 
Floated  barytes,  183. 
Frankfort  black,  188. 
Frankfurter  schwartz,  188. 
French  blue,  186. 
French  gray,  250. 
French  ocher,  183. 
French  red,  250. 
French  zinc,  34. 

G. 

Gamboge,  86,  183. 

properties  of,  86. 
Gas  black,  173,  188. 

properties  of,  173. 

uses  of,  174. 
Gazelle,  250. 
Gelben  ocher,  183. 
Geranium,  250. 
Giallo  di  napoli,  186. 
Glues,  220. 

general  remarks  on,  220. 

properties  of,  221. 

uses  of,  222. 


Glycerine,  228. 

properties  of,  228. 

uses  of,  228. 
Gmelin's  blue,  1S6. 
Gobelin  blue,  250. 
Gold,  250. 
Golden  brown,  250. 
Gommegutte,  183. 
Graphite,  179,  188. 

production  of,  179. 

properties  of,  180. 
Grass  green,  250. 
Gray  drabs,  250. 
Gray  green,  250. 
Gray  stone,  250. 
Green  bice,  186. 

Green   carbonate   of     copper,    186 
Green  earth,  186. 

Green    oxide    of    chromium,    134, 
186. 

properties  of,  134. 

uses  of,  134. 

Green  pigments,  129,  185. 
Green  stone,  250. 
Green  verditer,  142,  186. 

properties  of,  142. 
Greys,  250. 

Grinding  colors,  a  trade,  68. 
Griin  erde,  186. 
Grimes  chromoxyd,  186. 
Griins  pan,  186. 
Guimet's  blue,  186. 
Gum  arabic,  224. 

properties  of,  224. 

uses  of,  225. 
Gypsum,  46,  183. 

chemistry  of,  47. 

history  of,  46. 

properties  of,  47. 

source  of  supply,  46. 


H. 

Hay  color,  250. 
Heavy  spar,  183. 


INDEX 


261 


Heliotrope,  250. 
History  of  white  lead,  9. 
Honey,  227. 

properties  of,  227. 

I. 

Imitation  vermilion,  100,  184. 
Impurities  in  linseed  oil,  201. 

properties  of,  126. 

tests  for,  201. 

uses  of,  126. 
Indian  brown,  250. 
Indian  lake,  126,  185. 
Indian  pink,  250. 
Indian  reds,  110. 

characteristics  of,  110. 

production  of,  110. 

properties  of,  112. 

uses  of,  112. 
Indian  yellow,  87,  183. 

chemistry  of,  88. 

properties  of,  88. 
Indisch  gelb,  183. 
Iron  gray,  250. 
Italian  pink,  1$4. 
Italian  sienna,  187. 
Ivory  black,  175,  188. 

manufacture  of,  175. 

properties  of,  176. 

uses  of,  176. 
Ivy  green,  251. 

.1. 
Japans,  214. 

properties  of,  214. 

uses  of,  214. 
Jasper,  251. 
Jaune  brilliant,  184. 
Jaurie  d'antimoine,  184. 
Jaune  de  cadmium,  184. 
Jaune  de  cobalt,  183. 
Jaune  de  Mars,  183. 
Jaune  de  Naples,  184. 
Jaune  Indien,  183. 
Jaune  royal,  184. 
Jonquil,  251. 


K. 

Kaolin,  44,  183. 

properties  of,  45. 
King's  yellow,  93,  184. 

characteristics  of,  93. 

chemistry  of,  94. 
Kobalt  blau,  187. 
Kobalt  gelb,  183. 
Kobalt  griin,  185. 
Konig's  gelb,  184. 
Krapp  lack,  185. 

L. 

Lac  lake,  185. 
Lack  lack,  185. 
Lakes,  118. 

general  remarks  on,  118. 

manufacture  of,  121. 

red  lakes,  119. 
Lamp  black,  170. 

chemistry  of,  170. 

manufacture  of,  170. 

properties  of,  171. 

uses  of,  172. 
Lapis  lazuli  blau,  186. 
Laque  brown,  183. 
Laque  cramoisi,  185. 
Laque  de  garance,  185. 
Laque  d'Inde,  185. 
Lavender,  251. 
Lazurestein  blau,  186. 
Lead  color,  251. 
Lead   (sulphate),  see   sulphate   of 

lead,  26. 
Lead     (sublimed),    see     sublimed 

lead,  27. 

Lead  (white),  see  white  lead,  9. 
Lead  (white  oxide),  see  white  oxide 

of  lead,  28. 
Leaf  buds,  251. 
Leather,  251. 
Lemon,  251. 
Levant   umber,  187. 
Lilac,  251. 


262 


INDEX 


Linseed  oil,  191. 

boiled,  203. 

chemistry  of,  195. 

drying  of,  196. 

manufacture  of,  191. 

properties  of,  198. 

tests  for  impurities,  201. 

uses  of,  199. 
Liquid  dryers,  231. 

general  remarks  on,  231. 
List  of  principal  tints,  243. 
London  smoke,  251. 

M. 

Madder  brown,  185. 
Madder  lakes,  123,  185. 

properties  of,  124. 

uses  of,  124. 
Madder  purple,  185. 
Madder  red,  185. 
Magenta,  251. 
Malachite,  142. 
Manilla  or  deck  paint,  251. 
Marigold,  251. 
Maroon,  251. 
Mars  gelb,  183. 
Mars  orange,  183. 
Mars  yellow,  183. 
Mastic,  251. 
Mauve,  251. 

Medium  chrome  green,  185. 
Medium  chrome  yellow,  183. 
Metallic  browns,  166. 

manufacture  of,  166. 

properties  of,  167. 

uses  of,  167. 
Mexican  red,  251. 
Mignonette,  251. 
Miltos,  185. 
Mineral  yellow,  183. 
Mittes  green,  186. 
Mittler's  green,  186. 
Mixing  compound  tints,  239. 

general  remarks  on,  243. 

how  to  prepare,  240. 


Mixing  compound  tints  —  cont'd. 

in  distemper,  241 . 
Mixing  simple  tints,  239. 
Molasses  (see  honey),  227. 
Moorish  red,  252. 
Mortar  colors  made  from  ochers, 

75. 

Moss  color,  252. 
Mouse  color,  252. 
Mountain  blue,  187. 
Mountain  green,  186. 
Mulberry,  252. 
Myrtle  green,  252. 

N. 

Naphtha  (see  benzine),  208. 
Naples  yellow,  89,  184. 

chemistry  of,  89. 

history  of,  89. 

properties  of,  89. 
Neapel  gelb,  89. 
Neutral  tints,  236. 
New  blue,  186. 
Nile  blue,  252. 
Noirr  de  fumee,  188. 
Noir  d'ivoire,  188. 
Noir  de  vigne,  188. 
Normandy  blue,  252. 
Nut  brown,  252. 

O. 

Oak  color,  252. 
Ocher  jaune,  183. 
Ocher  roth,  185. 
Ocher  rouge,  185. 
Ochers,  57,  183. 

aluminous,  59. 

analysis  of  Oxford,  65. 

chemical  properties,  58. 

general  characteristics,  58. 

grinding  in  oil,  67. 

mining  of,  61. 

properties  of,  61. 

silicate,  58. 

uses  of,  63. 
Oil  of  turpentine,  207. 


INDEX 


263 


Old  gold,  252. 

Olive,  252. 

Olive  brown,  252. 

Opal  gray,  253. 

Opa,que  oxide  of  chromium,  186. 

Orange.  252. 

Orange  brown,  252. 

Orange  cadmium,  184. 

Orange  chrome  yellow,  183, 

Orient  yellow,  184. 

Oriental  green,  252. 

Orpiment  (see  king's  yellow),  184. 

Oxford  ocher,  183. 

Oxide  of  zinc  (see  zinc  white),  182. 

P. 

Paraffin  waxes,  219. 

characteristics  of,  219. 
Pariser  blau,  187. 
Paris  green,  143. 

chemistry  of,  143. 

preparation  of,  143. 

uses  of,  143. 
Paris  white,  182. 
Peach  blossom,  253. 
Peacock  blue,  253. 
Pea  green,  253. 
Pearl,  253. 
Peori,  183. 

Permanent  blue,  186. 
Permanent  weiss,  183. 
Permanent  white,  183. 
Permanent  yellow,  183. 
Persian  orange,  253. 
Pigment,  definition  of,  2. 
Pink,  253. 

Pink  madder  lake,  185. 
Pistache,  253. 
Plumbago,  188. 
Plum  color,  253. 
Pompeian  red,  253. 
Poppyseed  oil,  204. 

properties  of,  204. 

uses  of,  204. 
Portland  stone,  253. 


Powdered  silica,  183, 
Preface,  iii. 

Preliminary  remarks,  i. 
Primary  colors,  235. 
Primrose,  253. 
Prussian  blue,  148,  187. 

Listory  of,  148. 

manufacture  of,  148. 

properties  of,  149. 

uses  of,  149. 
Prussiate  of  iron,  187. 
Puiri,  183. 

Pulp  ground  white  lead,  16. 
Puree,  183. 
Purple,  253. 
Purple  brown,  253. 
Purple  lake,  185. 
Purpurin,  120. 

Q- 

Quaker  green,  253. 
Quercitron  lake,  184. 

R. 

Raw  sienna,  163,  187. 
Raw  umber,  156,  187. 
Red  chalk,  185. 
Red  hematite,  185. 
Red  iron  ore,  185. 
Red  lead,  116. 

chemistry  of,  116. 

history  of,  116. 

properties  of,  117. 

uses  of,  117. 
Red  ocher,  185. 
Red  oxide  of  iron,  114. 

properties  of,  114. 

uses  of,  115. 
Red  pigments,  95. 
Rinkman's  green,  185. 
Roan,  253. 

Robin's  egg  blue,  254. 
Roman  ocher,  185. 
Rose  lake,  123. 

properties  of,  123. 

uses  of,  123. 


264 


INDEX 


Rose  madder  lake,  185. 
Rose  pink,  122. 

properties  of,  122. 

uses  of,  122. 
Rouge,  184. 
Rouge  de  Venise,  184. 
Royal  blue,  155,  187. 
Ruben's  madder,  185. 
Rubrica,  185. 
Ruddle,  185. 
Russ,  188. 
Russet,  254. 
Russian  gray,  254. 

S. 

Sage  green,  254. 

Salmon,  254. 

Sap  green,  254. 

Sapphire  blue,  254. 

Saxon  blue,  187. 

Scale  test  for  adulterations : 

how  to  make  it,  81. 

in  colors,  80. 
Scarlet,  254. 
Scarlet  ocher,  185. 
Scheele's  green,  144,  186. 

characteristics  of,  144. 
Scheele's  griin,  186. 
Sea  green,  254. 
Seal  brown,  254. 
Secondary  colors,  235. 
Shellac  (alcoholic  solution),  215. 

properties  of,  215. 

uses  of,  215. 
Shrimp  pink,  254. 
Siccatives  (see  driers),  229. 
Sienna  erde,  187. 
Siennas,  161,  187. 

analysis  of,  162. 

burnt  sienna,  163. 
properties  of,  164. 
uses  of,  164. 

chemistry  of,  162. 

general  characteristics,  161. 

history  of,  161. 


Siennas  —  continued. 

properties  of,  163. 

raw  sienna,  163. 
properties  of,  163. 
uses  of,  163. 
Silicate  earth,  48. 

chemistry  of,  49. 

properties  of,  49. 
Silver  white,  182. 
Silver  white,  183. 
Sky  blue,  254. 
Slate,  254. 
Smalt,  187. 
Smalte,  187. 
Snuff  color,  254. 
Soluble   blue    (see   Chinese   blue), 

150,  186. 
Spanish  brown,  168. 

properties  of,  168. 

uses  of,  168. 
Spanish  white,  182. 
Spirits  of  turpentine,  207. 

manufacture  of,  207, 
Starch,  226. 

properties  of,  226. 
Stone  color,  254. 
Straw  color,  254. 
Strictly  pure  vs.  compound  leads,. 

24. 
Sublimed  lead,  27. 

properties  of,  27. 
Sugar  (see  honey),  227. 
Sulphate  of  barium,  183. 
Sulphate  of  lead,  20. 

chemistry  of,  26. 

properties  of,  26. 
Sulphate    of    lime    (see    whiting), 

182. 

Sulphide  of  cadmium,  184. 
System  of  packing  white  lead,  23. 

T. 

Table  of  synonyms,  181. 
Tally-ho,  255. 
Tan,  254. 


INDEX 


265 


Terra-cotta,  255. 
Terra  di  sienna,  187. 
Terra  ombra,  187. 
Terra  rosa,  187. 
Terra  verde,  186. 
Terre  d 'ombre,  187. 
Terre  de  sienne,  187. 
Terre  de  verone,  186. 
Terre  verte,  139,  186. 

analysis  of,  139. 

history  of,  139. 

production  of,  139. 

uses  of,  139. 
Tertiary  colors,  236. 
Turkey  umber,  156,  187. 
Turner's  blue,  187. 
Turquoise  blue,  255. 
Tuscan  reds,  112. 

manufacture  of,  112. 

properties  of,  113. 

uses  of,  113. 

U. 

Ultramarine  blue,  145,  186. 
chemistry  of,  145. 
manufacture  of,  145. 
properties  of,  146. 
uses  of,  146. 
Umbers,  156,  187. 
burnt  umber,  159. 

properties  of,  159. 
chemistry  of,  157. 
properties  of,  158. 
provenances  of,  156. 
raw  umber,  156. 
burnt  umber,  159. 
properties  .of,  156. 
uses  of,  158. 
Umbraun,  187. 

V. 

Vandyke  brown,  165,  188. 
properties  of,  165. 
provenance  of,  165. 


Vandyke  brown  —  continued. 

uses  of,  165. 
Varnishes,  210. 

general  remarks,  210. 

properties  of,  211. 

uses  of,  212. 
Vegetable  waxes,  217. 

characteristics  of,  217. 
Vehicles  for  mixing  pigments,  189. 
Venetian  red,  106,  184. 

history  of,  106. 

manufacture  of,  107. 

properties  of,  109. 

uses  of,  109. 
Verdigris,  141,  188. 

chemistry  of,  141. 

properties  of,  141. 

uses  of,  141. 
Vermilion,  95,  184. 

characteristics  of,  98. 

chemistry  of,  96. 

history  of,  95. 

source  of  supply,  95. 

uses  of,  99. 
Vermilion  reds,  100,  184. 

manufacture  of,  101. 

properties  of,  103. 

uses  of,  103. 
Vert  emeraude,  186. 
Vert  de  chrome,  186. 
Vert  de  cobalt,  185. 
Vert  de  gris,  186. 
Vert  de  Guimet,  186. 
Vert  de  Montpelliers,  186. 
Vert  de  Scheele,  186. 
Vert  de  zinc,  185. 
Vert  Panetier,  186. 
Vert  Paul  Verone,  186. 
Vienna  brown,  255. 
Vine  black,  188. 
Violet,  255. 
Viridian,  137,  186. 

properties  of  137. 

uses  of,  137. 
Volatile  oils,  206. 


266 


INDEX 


w. 

Water  green,  255. 
Waxes,  217. 
White  lead,  9. 

chalking  of,  21. 

chemistry  of,  11. 

cylinder  system  of  corrosion,  18. 

defects  of,  21. 

Dutch  process  of  corroding,  10. 

grinding  dry  in  oil,  15. 

history  of,  9. 

injurious  gases,  22. 

manufacture  by,  12. 

process  of  manufacture,  19. 

properties  of,  20. 

pulp  ground  lead,  16. 

ripening  oil  ground  lead,  16. 

stack  system  of  corrosion,  11. 

vehicles  for,  22. 

volatile  oils  for,  22. 

working  qualities,  20. 
White  oxide  of  lead,  28. 

hardening  in  package  when 

ground  in  oil,  28. 
White  pigments,  8. 
White  silicate,  183. 
Whiting,  41,  182. 

chemistry  of,  42. 

levigation  of,  42. 


Whiting  —  continued. 

mining  of,  42. 

properties  of,  43. 

qualities  of,  43. 

source  of,  42. 
Willow  green,  255. 
Wine  color,  255. 

Y. 

Yellow  bronze,  255. 
Yellow  lake,  184. 
Yellow  madder,  184. 
Yellow  ocher,  57,  183. 
Yellow  pigments,  57,  73,  183. 
Yellow  ultramarine,  183. 

Z. 

Zaffre,  187. 
Zinc  green,  135,  185. 
Zinc  Weiss,  182. 
Zinc  white,  32,  182. 

chemistry  of,  33. 

compounds  of,  38. 

defects  of,  37. 

history  of,  32. 

in  distemper,  39. 

manufacture  of,  33. 

properties  of,  36. 

tests  for  purity  of,  35. 
Zunzober,  184. 


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